Take shelter from Hawai'i's tropical heat under the massive canopy of largest Banyan tree on the island.

Scattered throughout London are ancient remnants of the city's former bounding wall.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

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

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

A mysterious suspended hand greets unsuspecting visitors at the Tower of London.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Only a few pieces remain of the structure that carried people and goods across the Thames for some 600 years.

A timeline of London history on the Thames Path, installed in 2014

A bronze bust commemorates the heroism of the secret agents who led covert operations against the Nazis.

At almost 1,000 years old, this is the oldest known door in all of Britain.

The "beautiful" equation predicting the movement of all electromagnetic particles is engraved in front of Newton's tomb.

This statue celebrating everyday life in Dublin has a few unsavory nicknames.

Experience what life was like in Ireland during the Viking and medieval ages.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.

A guitar mounted on a wall in Temple Bar honors the Irish musician.

The mummified heart of a saint lives on in this church—after a brief hiatus when it was stolen.

A mysterious plaque to the even more mysterious "Fr. Pat Noise," killed in "suspicious circumstances."

This is the place where U2’s lead singer got his nickname.

The modern birthplace of Irish freedom.

The enchanting archway is the only surviving portal into Dublin’s lost medieval wall.

This supermarket offers shoppers a window into the past alongside their groceries.

Some of the saint's blood and bones are said to reside in Dublin.

An enigmatic monument to the Irish revolutionary who plotted an uprising against British rule.