One of the first monuments dedicated to the accomplishments of the great Vice Admiral, Horatio Nelson.

A scattered trail of street art adds a pop of color to the city's stark structures.

This well-preserved Cistercian Abbey in a romantic pastoral setting has inspired artists like the poet Wordsworth.

Abandoned blockhouses from Nazi Germany's Atlantic Wall erode into the sea on a French beach.

Some of the greatest minds in the history of Hungarian art and science converged in this café.

This hidden art nouveau gem was designed by an architect in search of a national style.

Baroque celebration of the end of the Great Plague of Vienna.

The house that took a plunge into the facade of a museum.

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

Cold war icon and onetime "hole" in the iron curtain.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

Berlin's old airport.

An old department store turned Nazi prison turned artist commune.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

The first geometric self-supporting spiral stairs in Britain are a truly beautiful sight.

Shiny Brutalist box commemorates a pioneer of electricity and houses a railway transformer.

Originally built for London’s cab drivers, this bright green hut now serves anyone a hot drink or meal.

The library houses an incredible collection of some of the world's most impressive books and manuscripts.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.