Mysterious stone tower featured in many alternative histories of the New World.

Oldest synagogue in the United States.

The final resting place of one member of the Amistad slave revolt who never made it back home.

This 15-foot tall obelisk commemorating the Philadelphia-Baltimore railroad connection sat neglected for over a century.

Nursery with extensive collection of flesh-eating plants operated by the author of "The Savage Garden."

Hidden behind West Philadelphia rowhomes is a haven for migratory and local bird species both ordinary and rare.