The world's largest sticker ball weighs in at a mighty 231 pounds.

An abandoned saucer-shaped monument in the Bulgarian mountains.

This colossal ancient sculpture of the monstrous Aztec rain god has a literally stormy history.

Sandstone rock formations that look like they belong on the cover of a progressive rock album.

The site where a nuclear bomb was lowered over 8,000 feet underground and detonated as an experiment in natural gas extraction.

Even in death, he's still your huckleberry.

Take a dip in the world's largest mineral hot springs pool.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

The world's largest key collection features keys to the White House, Frankenstein's castle, and Hitler's bunker.

The giant stump of the once towering cottonwood where Ute people held tribal meetings.

A dangerous narrow-gauge railroad once traced a route through this striking canyon.

This naturally-sourced hot spring is now home to a clothing-optional resort.

A futuristic hovertrain is parked unceremoniously alongside a nondescript road.

Located in the world's highest-altitude Dark Sky Community, this observatory welcomes amateur and professional astronomers alike.

The largest self-built castle in the U.S., six decades in the making.

Possibly the world's only drive-in movie theater with an attached motel.

Scale replica of China's ancient terracotta tomb warriors and Forbidden City are the side project of an eccentric millionaire.

A fruit-loving town welcomes visitors with a giant melon set against the sky.

The saga of the massive nut begins and ends in Texas.

A tiny waterway named after a ghost story.

Tile mosaics and quotes from Pablo Picasso add an artistic flair to these bus stop benches.

The quirky gift from West Berlin for the 1968 World's Fair still stands in Hemisfair Park.

Minimalist modern art on a repurposed military base in rural Texas.

The highest point in Texas is capped by a big silver pyramid.