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Built in 1929, the almost unbelievably huge Goodyear Airdock in Akron, Ohio, was created as a space where blimps, airships, and dirigibles could be constructed, but building such a massive space created some pretty weird problems, such as indoor rain, and putting the whole thing on rollers so that it could expand and contract with the seasons. 

For a brief, beautiful moment in the early 20^th century, it really seemed like airships and zeppelins were going to be the future of air travel, with docking towers built in major cites and aspirational advertisements filling Americans with dreams of luxury sky balloons. It was this era that led to the creation of the Goodyear Airdock. The almost comically large hanger stands over 200 feet tall and well over 1,000 feet long, all without any interior supports like pillars or struts. At the time of its completion, the building was the largest of its kind in the world. The building holds over a million cubic meters of space in which to create massive lighter-than-air ships. To get the ships out of the airdock once they were completed, both of the rounded ends of the building actually slid apart like rounded wedge doors. Each of the doors weighed 600 tons, powered by their own separate power plants. Of course, construction on this grand scale created some surprising issues.

For one, the huge building was expected to expand and contract as the temperature changed, so much of the structure was placed on rollers so that it could do so without doing any structural damage. In addition, the temperature inside and outside the building would often be drastically different, creating a sort of indoor weather system. To combat this, rows of massive windows were installed on either side of the hanger which open up to equalize the temperatures. However, despite this, during certain conditions, condensation can accumulate in the upper air of the hanger and begin to "rain" on the builders below.

The Goodyear Airlock is not open to the public, but the monolithic black slug of a building can be seen by passersby on the highway.

For more on the Goodyear Airdock, visit Atlas Obscura!

More wonders to explore:

• The largest man-made crater in the U.S. is now radiation-free enough to visit.
• Midnight penguin parade. Nuff said.
• This derpy Swedish lion taxidermy was made by someone who had never seen a lion.