A cablecar-station-turned-revolving restaurant with 360-degree views of the Swiss skyline.

Since the 1700s, this old barrel has acted as a post box that relies on the kindness of travelers.

Once at the center of U.S. finance, the historic Trading Room was meticulously recreated piece by piece and rebuilt in the Art Institute.

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 massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

Fragments of architectural wonders from around the globe are embedded in the newspaper building's walls.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Illegal drag racing two stories beneath Chicago’s streets.

G.V. Black, the Father of Modern Dentistry, keeps an eternal eye on Chicagoan’s teeth from his perch in Lincoln Park.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

The sign to a demolished amusement park now stands in front of a local library.

A tribute to one granddaughter's old apartment which now represents the whims of each visitor.

An exhibit of items from the mental institution where Mary Todd Lincoln lived after her son conspired to have her committed.

This house renovated by Frank Lloyd Wright was the centerpiece of a lavish 20th-century estate.

World's second largest particle accelerator, where nature reveals its secrets.

Arguably the best example of an authentic Dutch windmill in the United States, rivaling its counterparts in the Netherlands.

This cemetery is all that remains of a school for "wayward" girls.

This singular Irish dolmen is more Frank Lloyd Wright than upright stonehenge.