An Art Nouveau gem hides beneath the layers of city grime obscuring this once-magnificent building.

A fountain standing as a testament to a doomed alliance.

Ancient serpentine sacrifice holder that has stood the test of time.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

A marvel of Byzantine engineering under the streets of Istanbul.

The ornate miniature mansions were built for Istanbul's feathered residents.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

A floating cat sanctuary on an Amsterdam canal.

A historic Montreal market that was the city's agricultural hub for over century.

A Montreal deli that was so beloved that it was allowed to circumvent their laws of language.

This small glass cube is a peaceful out-of-the-way sanctuary at the busy airport.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

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

This headstone marks the grave of an 11-year-old boy killed during clashes in the streets over the boycotting of British goods.

The former site of an all-but-forgotten colonial landmark is now remembered by an often overlooked bas relief.

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

Each August, one of the largest religious (and food) celebrations in the country is held in Boston.

This impressive Boston holy house is the American mecca for Christian scientists.

Statue commemorating the use of ether in anesthesia.

American revolutionaries and British soldiers alike are buried here in the fourth-ever cemetery in Boston.

One of the last remaining World War II Victory Gardens in the U.S. is quietly growing across from Fenway Park.

Historic Hull Street was actually the first street with a proper name in the Boston area.

A former waterfront market is now in the center of town due to some interesting Boston engineering.