The Gloriously Blocky Ships That Carry Cars Across The World Are More Brilliant Than You’d Expect

The world of shipping is something beautiful that most people never have to worry about. The products that we use every day, from the cars we drive to the food we eat, just magically arrive at stores and at our doors. Global car shipping is a massive business, and the ships that make it work are actually brilliant pieces of engineering. Here’s what’s so fascinating about the gigantic floating parking lots that ship thousands of cars at a time around the world.

I’m counting down the days until I can drive to Baltimore and pick up my latest loot, a 1997 Honda Life. I’m so excited that I keep checking a vessel tracker to confirm that, yep, my car is still somewhere on the Pacific Ocean. Its ship, the MOL Clover Ace, should arrive in Panama somewhere around May 10 before entering the canal and making headway to the American East Coast. Assuming all goes well, I’ll be picking up my car during the first week June or so.

I’ve been falling down a rabbit hole of shipping topics lately, and something that has really reeled me in is realizing just how awesome roll-on roll-off vessels are. These ships are essentially giant parking lots where cars, trucks, railroad cars, construction equipment, and more are driven and pulled onto the ship’s several decks, where they’ll be lashed down for a long voyage. Usually, car sites won’t write about the so-called RoRo unless something bad happens, like a fire or a capsizing, and that’s a shame. These ships enable the global car trade to happen, and the world would be a very different place without them. So, let’s look at why RoRos are marvels of engineering.

Fulfilling A Need

The greatest innovation the RoRo has brought to the world of shipping is the easy transfer of thousands of vehicles from the ground, onto the ship, and then back onto the ground again. As I noted above, vehicles are simply driven up a ramp and right onboard. But, if you had to ship a car in the times before the RoRo, the process was very different.

The RoRo as we know it was an invention that came into popularity after World War II, but the concept of a ship in which vehicles roll in and then roll out wasn’t anything new.

Most sources report that the concept of the RoRo was invented in the 1830s as the train ferry. According to Shipping magazine, the Monkland and Kirkintilloch Railway hauled coal along a short route on the Forth and Clyde Canal in Scotland. In 1833, the railroad found a solution for getting the rail wagons across the canal by rolling the wagons onto a barge and then rolling them off. This comparatively primitive method to carry train wagons over water is considered to be the genesis of the RoRo.

The first modern train ferry was the PS Leviathan, which was built in 1849. The Edinburgh, Leith and Newhaven Railway wanted to be able to cross the five-mile-wide Firth of Forth in Scotland to access ports on the other side. However, bridge technology hadn’t existed yet to permit such a crossing. Engineer Thomas Bouch pitched a novel idea. There could be custom-designed slips at a departure port and an arrival port, which would permit the loading of railcars onto the deck of a special steamship. The cars would be loaded and chocked. The ship would then sail five miles to the other side, where a clone of the slip was used to pull the railcars off of the ship.

Thomas Bouch designed the slips, which used stationary steam engines to pull railcars onto the ferries designed by Thomas Grainger. The ramp and gantry system utilized to load the ship compensated for tides by moving up and down the bank. Apparently, it took about seven minutes to load up to 40 train cars and another 25 minutes for the ship to complete the crossing. In February 1950, the Floating Railway opened for business.

It’s noted that Bouch did not invent the train ferry, but he did figure out a practical way to make the idea work. Train ferries would catch on, with more train ferries getting built in Europe. The idea spread around the world, including to ferries built in Russia and Switzerland. The roll-on roll-off train ferry even made its way to America, where train ferries would become a part of getting trains across the Great Lakes and other bodies of water.

The train ferry would also become an important vehicle in World War I. The Allies figured it was much easier to roll artillery and supplies onto ferries on railcars than it was to lift those supplies into ships the traditional way.

Before the advent of the RoRo, vehicles were treated like any other cargo. The vehicle would be strapped to a crane and then hoisted into a ship’s cargo hold just like anything else.

But this method is highly inefficient for both railcars and motor vehicles when they’re perfectly capable of simply rolling into and out of the ship. If a ship’s cargo was nothing but vehicles, it would be substantially faster to just drive those vehicles onboard than it would be to hoist them in one at a time.Despite the successes of the train ferry in the early 19th century, it would take much longer before the same concept was applied to shipping cars. Indeed, even as many railcars were simply rolled onto ships, cars still had to have their fuel tanks drained before they were lashed up to a platform and hoisted into a ship. At the same time, it wasn’t like automakers of the 1910s and 1920s had a need to ship millions of cars across the world, either.

Landing Ship, Tank

For many ship historians, some of the first practical motor vehicle RoRo ships were known as the “Landing Ship, Tank.” The U.S. Army explains:

On July 10, 1943, the invasion of Sicily began with an assault by four U. S. Army Divisions, four British divisions and a Canadian division. Soldiers, equipment and supplies were transported to the island by a force of 3,200 ships and craft, including a new type of amphibious ship, the Landing Ship Tank, commonly referred to as an “LST.” Its maximum speed of 11.5 knots also produced the nicknames “Large Slow Target” or “Large Stationary Target” by the soldiers. The invasion of Sicily was the first large scale use of LSTs in a joint operations amphibious landing in the European-African-Middle Eastern Theater of Operations.

Its design and construction had been a joint operation. It was designed at a British-American conference in November 1941. America built all of the vessels for both countries. The first keel was laid down on June 10, 1942 and by the end of World War II, 1,051 of the vessels had been built. LSTs enabled assault troops to avoid heavily defended ports and to land wherever there was a suitable beach.

The LST was specifically designed to land vehicles. It was 328 feet long, and could carry armored vehicles in the tank deck and non armored vehicles on the main deck. The cargo capacity was 2,100 tons and approximately 200 soldiers. Its heart was the Tank Deck-a space 230 feet long by thirty feet wide by twelve feet tall. Once it arrived at a beach, the massive bow doors opened and the vehicles drove off ready for combat.

A great article by Commander Kendall King, U.S. Navy details what it was like to ride in the LSTs. The vessels rolled 40 degrees in waters that other sailors in other ships didn’t even notice. Commander King also gives credit to Winston Churchill for the initial idea as Churchill had quite the addiction to the idea of using landing craft to deploy infantry and tanks onto beaches where few would see them coming.

Despite the vulnerabilities of the LSTs, the Army notes that only 26 were lost during battles and only another 13 were lost due to an accident or weather. What was clear was that the LSTs had incredible potential. Why load vehicles into a ship’s hold when you can just drive them onboard? The value of this was further demonstrated after the war when soldiers coming home from World War II drove cars onto train ferries and then drove them off when the ferries reached their destinations.

LSTs Find A New Life

As the Royal Museums Greenwich explains, some of the earliest car roll-on roll-off ships were just repurposed LSTs:

Colonel Frank Bustard (1886-1974), the founder of the Atlantic Steam Navigation Company (ASN), joined the White Star Line in 1902 as an office apprentice. Bustard left the White Star Line on its merger with Cunard in 1934 and formed the Atlantic Steam Navigation Company in 1936. His business model was to offer cheaper travel across the Northern Atlantic but his plans were changed by the outbreak of war in 1939.

Chartering, and then modifying, three tank landing ships at the end of the war, Bustard won a contract to return military vehicles and effectively launched the first roll-on-roll-off service for road vehicles with the first voyage of the Atlantic Steam Navigation Company taking place in 1946 when the Empire Baltic was used to ship vehicles from Tilbury to Rotterdam. The fleet expanded to include further modified landing ships and purpose-built vessels designed to carry freight and passenger vehicles and with on-board accommodation.

The first voyage of the Atlantic Steam Navigation Company departed on September 11, 1946. The ship was Empire Baltic, formerly LST 3519, and she took on a load of 64 cars for the Dutch government. Her sisters included Empire Cedric, and Empire Celtic, two other LSTs that were chartered for use delivering cars. Later, they would be joined by another converted LST, the Empire Doric.

Empire Cedric was a particularly special ship. She was bestowed with a passenger certificate, allowing her to carry 50 passengers. Because of this, Empire Cedric holds the distinction of being the first known instance of a commercial combination passenger roll-on roll-off ship.

Soon enough, vessels would be built specifically for the purpose of hauling cars, trucks, and semi-trailers. In 1956, the small Searoad of Hyannis was able to transport a handful of vehicles between Hyannis, Massachusetts, and Nantucket Island.

As shipping news publication Freight Waves writes, the 1960s brought on a need for a new kind of RoRo ship. Until that point, RoRo ships were relatively small and could carry only a modest number of vehicles. This was a problem for Europe and Japan, as the regions had begun exporting vast numbers of vehicles. Existing RoRos were too small and weren’t really built for this sort of task. Meanwhile, typical cargo ships still required cars to be hoisted onboard, which took forever.

The answer to this problem would come from the bulk carrier trade. If you could ship literal tons of coal, containers, or other material relatively easily, what if the same concept were applied to cars?

Carrying Cars In Bulk

The first bulk car carriers were little more than converted bulk carriers. These ships would sail from the United States to Asia or Europe with coal, grain or soybeans. Then, once those goods were unloaded, the ships’ cranes and derricks would lower cars into the ships’ holds. These ships used special decks that were lowered down on chains to allow for multiple levels of cars to be shipped. In doing so, journeys in which these ships might have been empty now had cars.

But the problem here continued because while these ships had greater capacities, they weren’t RoRos and loading them took forever. These types of ships are known as lift-on lift-off ships. Thus, the next evolution was to combine the bulk carrier with the RoRo. Wallenius Lines AB claims to have the very first RoRo ship built specifically to haul lots of cars across an ocean. This ship was the MS Aniara, which was built in 1963 by AB Lödöse Varf, Lödöse.

She was a small ship by today’s standards, measuring only 248 feet long and 38 feet wide. But, crucially, the Aniara had combined the best of both worlds. She was large enough to carry 240 cars like a bulk carrier. But like the smaller LSTs that were converted into RoRos, the Aniara was designed so that cars and trucks drove right onto the Aniara’s decks, dramatically shortening loading times.

Many consider the Aniara to be the very first class of ship known as the pure car carrier, or PCC. As you can guess, the entire purpose of the PCC is to carry nothing but cargo that can be rolled onto and rolled off of the ship, typically using ramps carried by the ship itself.

As global car exports increased, the size and design of the PCC grew with it. In 1970, Japan’s “K” Line commissioned the Toyota Maru No. 10 from the Kobe Works of Kawasaki Heavy Industries. The Toyota Maru No. 10 looked more or less like the ancestor of today’s great blocky RoRos. The ship featured multiple self-deployed loading ramps and vehicles were driven onto the ship and parked on the ship’s multiple decks. “K” Line claims that the Toyota Maru No. 10 was a game-changer for car exports as the RoRo design reduced damage caused to vehicles during shipping and dramatically cut down turnaround time. “K” Line continues by saying that the ship was an inspiration for further PCC development.

Just three years later, “K” Line commissioned its next great RoRo, the European Highway. This ship was famous because, at the time, its 4,200-car capacity made it the largest car carrier in the world.

The Modern Car Carrier

Since then, car carrier development has gone in some fantastic different directions. There is the pure car/truck carrier, or PCTC, ginormous box-shaped ships designed to carry cars, but also heavy construction and trucking equipment. Some of these ship feature decks that can adjust their heights to accommodate taller vehicles.There are also wild variations on the RoRo concept. Some RoRo ships are combination “ConRo” ships that will carry cars in the ship’s internal holds and containers outside on top. There’s also the RoPax ship, and these carry both people and cars. RoPax ships are more commonly called ferries, but also technically includes ships that would be carrying cars for freight purposes that also carry passengers. Believe it or not, there are some cargo ships out there with some passenger accommodations!

Höegh Autoliners has a reputation for running the world’s largest car carriers. In 2021, my 1989 Suzuki Every was brought to America aboard the Trapper, which can carry 8,500 CEU. In shipping, size is usually determined in either tonnage or in twenty-foot equivalent units (TEU) if we’re talking about container ships. RoRo ships measure size in car equivalent units (CEU).

For a fun fact, the standard for CEU is the footprint of the 1966 Toyota Corona, one of the first car exports to be shipped in the specialized PCCs. In other words, the Trapper can hold roughly 8,500 1966 Toyota Coronas.

The Trapper was once known as the world’s largest PCTC, but it has been beaten by the Höegh Aurora, which manages an impressive 9,100 CEU. The Aurora went into service only just last year and aside from her huge size, Höegh Autoliners says that the ship cuts down on emissions per car by 58 percent and the ship’s engines are multi-fuel units designed to run on liquefied natural gas (LNG) and low-sulfur oil.

Don’t worry, I won’t leave you hanging. The Aurora is powered by a Mitsubishi 8UEC60LS inline-six good for 19,140 HP at 100 RPM. That’s good to get the behemoth 656 foot, 25,200 deadweight tonnage 22.1 mph. Aurora also has a whopping 14 decks for cars and trucks.

Mitsui O.S.K. Lines offers a great explainer of the anatomy of a modern car carrier:

1) Multi-layered deck structure
Large ships have a multi-layered deck structure with 12 to 14 layers, which enables them to carry a large amount of cargo. In addition, environmental factors and the special nature of the cargo (damage liability) are taken into consideration.

2) Flooding and Fire Prevention Compartments (Gas Tight Door, Water Tight Door)
Compartments are provided to prevent flooding and fire from spreading in the event any trouble occurs.

3) Liftable deck
The height of some decks can be changed to accommodate large trucks and construction equipment other than passenger cars. 1 deck is divided into about 30 panels and operated by a lift car.

4) Inner Ramp (Slope)
An aisle is used for vehicles to move and load between multiple decks, with a ramp angle of 10 degrees.

5) Shore Ramp
A shore ramp is a bridge that passes between the quay and the vessel and allows cars to be driven onto and off the vessel for loading and unloading. The ramp is part of the ship’s hull, and it is designed to accommodate the height of the quay wall at Kanda Port in Fukuoka prefecture, the largest port in Japan.

6) Lashing facilities
Lashing points are provided on each deck for fastening vehicles. Vehicles loaded on the vessel are lashed (tightly bound) using lashing belts to prevent them from moving during the voyage.

7) In-hold ventilation
Ventilation is provided not only during the loading and unloading of cargo but also during the voyage itself, to expel exhaust fumes from vehicles during loading and unloading and evaporating gasoline fumes in the hold during the voyage.

8) Firefighting equipment
Early detection and initial extinguishing of fires is extremely important should an accidental fire break out, such as in the event of a vehicle collision or an electrical fault in the hold. For this reason, the ship is equipped with a fixed fire extinguishing system, portable fire extinguishers, and fire detectors.

Sadly, what makes RoRo vessels great is also their weakness. If those large loading doors aren’t properly secured, the ship can take on water, and the huge, open decks that are great for vehicle loading can be a disaster if water breaches the ship. Even worse, water sloshing about on those decks could lead to a free surface effect — that’s the movement of water in relation to pitch and roll changes — piling up and capsizing the ship. This is what happened in the MS Herald of Free Enterprise disaster in 1987. Thankfully, since then, improvements have been made to RoRo designs including watertight ramps and divided deck compartments.

Still, some seafarers refer to RoRos as “roll on/roll over” ships, which, ouch.

Controlled Chaos

The operations surrounding these ships are equally impressive. When a RoRo gets to a port, hundreds of port workers known as stevedores go through an elaborate process to load and unload vehicles. Sometimes, these teams may have less than a day to load over 1,000 vehicles, so there’s no time to waste.

When it comes to loading, heavier vehicles such as commercial trucks, commercial equipment, farming equipment, and specialty trailers carrying heavy loads will be loaded onto the main deck as well as in the lower decks. Of course, the logic here is to keep the heaviest weight down low for stability. These heavy vehicles are also spread out to reduce the stress moment on the ship’s structure.

The loading of a RoRo is handled through delicate calculations not only to ensure the vehicles are loaded and balanced safely, but also that they are parked in a manner so as to not block loading pathways when the loading is complete. Mistakes could lead to stevedores having to move potentially hundreds of cars, which takes hours and can delay the ship.

Life on these ships can get interesting as well. You’d think that RoRo ships would be boring because they’re just huge blocks full of thousands of cars. And sure, one of the jobs of the crew is to regularly check the cars to make sure none have shifted. The crew of a RoRo will also see their shipmates much more than they’ll see their own families. Remember, these voyages can last for longer than a month, and you’ll be surrounded by nothing but water and cars. Crews may be with each other for four months at a time.

But there’s also fun to be had. RoRo crews can enjoy good meals from the cook, play basketball on the upper deck, and generally enjoy each other’s company. I highly recommend watching this episode of Mega Transports above to learn more about how the operations of RoRos work.

I think you can see why these ships excite me. They really are like giant parking structures with hulls and gigantic engines. They move thousands of cars across the world and usually do it with such controlled chaos that you never even really hear about them until something goes wrong. The RoRo is a modern marvel, and my heart goes out to all of the dedicated people who make them work.

Top graphic image: Hoegh Autoliners