Rare recess caves fill this unbelievably beautiful Ohio park.

This dilapidated castle-like structure overlooks the Hudson River at one of its widest points and was once home to nuns.

America's greatest forgotten garden and the former stomping grounds of Son of Sam.

Along the Palisades skyline are the ruins of a large mansion built in 1911 and demolished in the 1930s.

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.