One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

Launched by Napoleon's soldiers more than 200 years ago, a cannonball remains embedded in the tower wall.

The largest fountain in Bratislava.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

Thousands of slain Soviet soldiers are buried within the shadow of this enormous obelisk.

Also known as the Blue Church, the building was consecrated to the daughter of Andrew II.

A giant glider—designed by the father of the Rubik's Cube's designer—now soars within a shopping mall.

The largest statue of this convex, homogeneous object with just one stable and one unstable equilibrium point.

This quiet, unassuming spot in Budapest was the birthplace of the bloody 1956 Hungarian Revolution.

The inverted pyramid design of this station stands out amid Bratislava's urban landscape.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

CERN's beautiful, bending sculpture is a tribute to the spread of knowledge.

This statue of a Hindu cosmic dancer at CERN is a metaphor for modern physics.

The World Wide Web was created in this nondescript corridor at CERN.

This colorful but controversial ceiling has been likened to a 21st-century Sistine Chapel.

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

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

A statue in the center of Dublin dedicated to one of their favorite sons of rock & roll.

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

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

An ancient neolithic tomb that only sees the sun twice a year.

The ancient tomb acts as a calendar that keeps perfect time.

Vibrant street art created with mixed media.

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.