Eons ago, a rushing lava river formed this pristine passage through solid rock.

Experience a charming 1930's version of "infotainment."

One of the last free public hot springs is decorated with hippie art.

Four hundred granite steps were built into this massive rock by the National Park Service.

Quite simply the largest tree in the world (by volume).

Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

San Francisco's newly reopened hands-on science museum.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.