America's post-nuclear-attack chambers of Congress.

This surprising gem is a world-class archeological museum hidden at the University of Chicago.

Cemetery featuring rare glass-fronted columbarium.

What's left of the ruins of the 1893 Columbian Exhibition, or World's Fair, also known as the White City.

A shining sculpture made of 3,115 lights, the number of visible stars in the Northern Hemisphere.

Chicago's largest cemetery is full of beautiful Victorian monuments and more than a few ghost stories.

A century-old hotspot for jazz, frequented by everyone from Charlie Chaplin to Al Capone.

An enormous park-like oasis, full of famous Chicagoans' graves.

An antiquated German apothecary on Chicago's North Side.

A Bibliophile's Dream.

A speakeasy takes on Chicago's drinking culture.

A lush green oasis in the middle of Chicago.

This shop for all your super spy needs hides an educational secret.

Abandoned 19th century homes once occupied by naval officers, soon to be demolished.

Devotional offerings and pleas for intercession are left at this Depression-era shrine inside a nature preserve.

This striking arch, one of the first architectural elements constructed in Prospect Park, was recently restored to its original glory.

During the American Revolution, this mansion hosted failed peace talks between the British and Americans.

Once thought to be the fabled Holy Grail, it is now known to be an oil lamp.

This old estate is a remnant of when the Bronx was a popular summer destination for wealthy New Yorkers.

This 19th century brick building in Brooklyn stands out like the anachronistic landmark that it is.

This study room in the New York Public Library saw the creation of one of contemporary America's greatest traitors.

The home of the first American-born saint is one of the only curved buildings in New York.

This hidden oasis features a stunning view of the Hudson River and the Palisades from a castle-like museum.

The former home of the reclusive "Weird Wendels" who dominated New York real estate a century before Donald Trump.