These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

This tree was grafted from the actual tree that led Isaac Newton to ponder the theory of gravity.

Local legend says Isaac Newton built this footbridge without any screws, bolts, or nails.

Numberless clock creates a meal of time for the dreaded, insectile Chronophage.

A "miracle" that seems to produce more holy fistfights than holy revelations.

The ancient latrines of the Greeks, in all their public glory.

A charming beach town in Turkey captures all the colors of the rainbow.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

An ancient necropolis of magnificent tombs.

A quirky bookstore hidden beneath a sea of whitewashed Greek villas.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

A controversial memorial at the place where Captain Cook met his violent end.

These ancient sacred grounds granted amnesty to those who managed to reach them.

Quite simply the largest tree in the world (by volume).

The second-largest giant sequoia in the world.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

The Jewish section of the famous Boothill Graveyard was abandoned for nearly 100 years.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

An old saloon in the West filled with history, and according to some, a few dozen ghosts.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.