The Bathtub

The Bathtub refers to the underground foundation area at the site of the World Trade Center and accompanying buildings in New York City.

[2] The South Tower of the World Trade Center was actually built around the PATH tubes that passed through the foundation area, thus service was uninterrupted throughout the whole of the construction period.

Today, a passageway leads between Brookfield Place and the World Trade Center Transportation Hub.

Once constructed, the bathtub walls relied on the presence of the basement floors of the WTC to give lateral support.

When these were partially destroyed following the collapse of the Twin Towers during the September 11 attacks, it was feared that removing the resulting debris pile could weaken the walls and cause them to fail, endangering workers and possibly compromising other buildings and flooding a significant portion of the subway system.

1969 view of the original WTC bathtub looking northeast. The frame of the south tower is on the left. PATH eastbound tunnel F can be seen in the center, penetrating the slurry wall on its way up Cortlandt Street to Hudson Terminal.
1969 view of the original WTC bathtub looking northwest. Note PATH eastbound tunnel F supported on a temporary trestle in foreground. Slurry wall with tie-backs can be seen on the left, and the frame of the north tower in the background. Also note the since-removed elevated west-side highway, which ran above West Street (today's West Side Highway).
The "Bathtub" at the National September 11 Memorial & Museum
Deep subterranean structure consisting of deep and shallow foundation beneath the Austin J. Tobin Plaza and the two towers