Century-old pillars in the depths of Van Cortlandt Park have been restored.

About a five-minute walk into the park will reveal the stones that have been present since 1905.

"There's 13 stones here," says Christina Taylor, executive director of Friends of Van Cortlandt Park. "Ten are granite, one is marble and two are limestone."

Their placement started as a test to see which type of stone could best weather a New York winter and eventually be used in the construction of Grand Central Terminal. Taylor says one of the granites was picked for the bottom part of the terminal and a limestone was chosen for the top layer, mostly due to its lower cost.

But the stones disappeared under layers of graffiti over time. Taylor says the Parks Department doesn't have the resources to clean the graffiti and instead painted over it.

A solution came in the form of funding from the Claire and Paul Porzell Foundation that allowed the Municipal Arts Society and Taddei Arts Conservation to clean off the graffiti and reveal what types of stones are underneath.

"Once it was cleared off, it was really cool to be able to see that there actually are different types of stone and they do look different," Taylor says.