Resonating tubes make music from highway overpass.

This small section of the Sleepy Hollow Cemetery is rotten with famous authors' graves.

This massive World War II calculator hearkens back to the days when "computer" was a job title.

A historic bridge with a lovely acoustic anomaly.

These impressively detailed battle scenes depict the violence and tragedy of war in miniature.

19th-century operating theatre in which the use of ether was first demonstrated - plus, a skeleton and a mummy!

Three prestigious academic collections come together to create a world-class natural history museum.

An eccentric inventor's castle home with its own indoor weather system.

Two thousand artifacts from around the world collected by one woman who loved to travel.

One of New York's best collections of pinball is hidden in a secret bar in the back of this laundromat.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

A room hidden behind a swinging shelf in the children's section.

A reliquary of pop culture marvels, including the world's largest (and most terrifying) Jack-in-the-Box.

Celebrating an art form with a collection of puppets from all over the world.

Hidden behind a Target are pillows of cooled lava that formed at the bottom of a deep lake in the Mesozoic Era.

A tiny memorial for the year the Connecticut River almost destroyed New England.

This lovely hilltop tower was specifically built to withstand 100 MPH winds.

The remnants of a 19th-century ironmaking complex hidden in the woods of Connecticut.

This opera house along the banks of the Connecticut River has two Tony Awards to its credit but it’s never staged a single opera.

Thousands of American timepieces on display in the former clock-making capital of the country.

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

An antique narrow gauge railway line still running through the Colorado and New Mexico mountains.

Take a steam-powered ride straight out of the past on this Appalachian rail line.