Photo via Sclafani's Flickr

The Putnam Trail in Van Cortlandt Park contains many rail remnants (including an old passenger platform) from the New York Central Railroad's Putnam Division, which began construction there in the 1870s. Amongst the historical artifacts that remain in the overgrown trail are 13 stones that were placed there prior to 1903 by Commodore Cornelius Vanderbilt. He had quarries send him samples to help determine which weathered best, with the chosen one used as the building material for Grand Central Terminal. "In the end, the second southernmost stone, Indiana limestone, was chosen not for its durability but for its cheaper transportation cost across Vanderbilt's railways." Who knew we had our very own Stonehenge in the Bronx!