San Francisco's Foundation is Built on Old Ships from the Mid-1800s

In 1994, construction workers in San Francisco's financial district began digging to build a new light-rail tunnel beneath the city when they hit something. It was a massive ship named "the Rome."

The ship was so large that the crew had to tunnel through the ship's hull to construct the tunnel. Now, the J, K, L, M, N, and T trains all ride through the hull of this ship every day.

But why was there a ship buried beneath the city, and how did it get there? To understand that, we have to travel back in time nearly 200 years.

The origins of San Francisco's ships

When the gold rush began in 1848, thousands of people sailed into California, hoping to strike it rich. The ships that sailed there were often just enough to get the crew there. Many would never sail again.

A large portion of the ships that landed in San Francisco Bay were simply left to rot as the crews they brought got caught up in gold fever. At the height of the gold rush, there were 500 to one thousand ships moored in the harbor, clogging up traffic and making the waters almost un-navigable.

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The city needed land, and since most of it had already been built on, politicians devised a brilliant solution: start building on the water. The city started selling plots of bay water on the condition that the new owner would turn it into new land. So, ships were intentionally run aground and built into hotels and bars – they became part of the city.

One of the most famous examples is that of a ship named the Niantic. This ship was run aground in 1849 and used as a warehouse and a hotel. Nicer ships in the harbor were turned into permanent structures and became as much a part of San Francisco as buildings built on the original land.

The fire of 1851 changed everything

All that was fine until a massive fire broke out in 1851. The fire gutted nearly the entire city, and most of the ships sank into the bay. When the fire was finally put out days later, much of the wreckage was covered with earth from nearby hills to start the rebuilding process. This resulted in many still intact ships, like the Rome, ending up buried beneath the now ground of the city.

In total, it is now estimated that there are 40-to-70 ships buried beneath San Francisco's financial district. Recent research has actually revealed the near exact locations for many of the ships. Some are clustered together while others rest alone under the city.

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So, much of San Francisco used to be ships run aground, but after a fire in 1851, those old ships now form the foundation to one of the most expensive real estate markets in the entire world.