With wetlands, wildlife and Liberty Science Center, Liberty State Park is teeming with opportunities for scientific exploration. But few people know that the park is also home to an important historical site. Located in the southeast corner of Liberty State Park, the site of the Black Tom explosion marks an important, but often forgotten, moment in United States history.

Officially, the United States was a neutral party in World War I until it formally entered the conflict in 1917, but the U.S. was involved in supplying war materials long before that. Black Tom, a small island located just off the coast of New Jersey, consisted of a complex of warehouses, barges, and railroads filled with a few million tons of war materials set for transport to Great Britain and France.

On July 30, 1916, German agents targeted and infiltrated the area, and their work resulted in one of the worst acts of sabotage in U.S. history. They succeeded in their aim to disrupt the U.S.’s provision of munitions, but they also caused a lot of other damage.

The force of the explosion was so strong that it blew out windows in Times Square and shook the Brooklyn Bridge, and pieces of shrapnel from the blasts not only destroyed a wall of Jersey City’s City Hall but also caused damage to the Statue of Liberty. Visitors were never again allowed to access the statue’s torch, and immigrants at nearby Ellis Island had to be evacuated. Vibrations from the explosion traveled all the way to Philadelphia, and the sound of it could even be heard in Maryland. Estimates place the explosion at the equivalent of an earthquake between a 5.0 and a 5.5 on the Richter scale.

Although this huge blast is often a forgotten piece of U.S. history, that wasn’t the case last weekend. This year marks the 100th anniversary of the attack, and on Saturday, July 30, Liberty State Park held a ceremony in remembrance. For photos of the event, click here.