A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

A 30-year-old Sycamore tree grown from a seed taken to the moon and back.

Pizza with a side of fine art.

This morbid, delightful curiosity shop offers everything from animal bones to human teeth.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

This historic hotel invented the chocolate brownie.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

All of Chicago's wood-paved streets are long gone but two alleys remain.

A little-known subterranean street runs under some of the best-known buildings in Chicago's River North.

These pretty kitties killed and ate as many as 135 railway workers.

Built to house a chapter of the Knights Templar, this grandiose building is a relic of Freemasonry in Chicago a century ago.

A century-old network of freight tunnels underneath the city's historic business district.

The palatial McDonald's that inspired Wesley Willis.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.