Home to items never before seen by the public.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

The walls of the iconic dome are hollow and have a secret stairway.

A Nessie-like monster supposedly lurks in this lake.

I-95's Tijuana-style celebration of kitsch at the Carolina border.

This research center for rare prosimians is studying how they sleep to help prolong human life.

One of the few surviving original NASCAR dirt-track speedways.