The attic of a four-century-old canal house hides a clandestine church.

Museum preserving torture methods from the past.

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

This surreal statue brings a famous French novel about a supernatural cad to arresting life.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

Indents in the pavement are all that remain from a grisly death machine in Paris.

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

The oldest Hindu temple complex in Nepal serves as the seat of Nepal’s national deity, Lord Pashupatinath.

This historic square in Nepal is home to temples dating back to the third century.

One of the largest Buddhist stupas in the world keeps an eye out in every direction.

This elegant neoclassical garden is a peaceful oasis in the middle of the Nepalese capital.

Sacred Buddhist home of some spiritual monkeys.

Even though some of the buildings date back to the Victorian era, this research institute is still involved in cutting-edge astronomy research.

This mundane post marks the old location of the city's main postal hub.