If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

An encyclopedic collection of mammal penises.

Walk in the footsteps of the gods and straddle two tectonic plates.

Strange rock formations tower above the river that snakes through this enchanting Icelandic canyon.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Medicinal spa created with the discharge from a geothermal energy plant.

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

Around 160 years ago, this spot marked the location of a wharf along the shores of the Charles River.

An enormous, inside-out glass globe built in 1935.

The first bell ever cast in Boston was cast by Paul Revere...and sounded terrible.

An interesting decoration on this historic site, this weathervane comes with as many legends as it does questions.

The remnants of a Gilded Age elegance preserved in the middle of a stark modern tower.

A tiny plaque marks the location of the water source that facilitated the birth of modern-day Boston.

Dedicated to one of the darkest moments in Irish history, this memorial has faced its fair share of backlash.

America's original house of worship for Spiritualism, the religious movement based on communing with the dead.

In 1958, an MIT fraternity pledge laid down on this bridge and instituted a new, unique unit of measurement.

This bridge was the birthplace of a unit of measurement based on a fraternity joke.

The oldest playground in America.

This Dutch-styled residential building was originally a cocoa company's World's Fair showpiece.

Ralph Waldo Emerson spent two years living here decades before it became a Frederick Law Olmsted-designed park.