Stonehenge

• One of the United Kingdom's most famous prehistoric monument is Stonehenge. Located in Wiltshire County, Stonehenge is a collection of stone monoliths in a circular formation. The exact date of Stonehenge's completion and purpose are unknown. According to National Geographic, the archaeology community believes Stonehenge was built approximately 4,600 years ago. Some of the possible purposes for Stonehenge include a ritual site and astronomical observatory.
  
  

Colosseum

• The Colosseum in Rome, Italy, was built by the Ancient Romans during the reigns of Emperors Vespasian and Titus from 72 to 80 A.D. Originally known as the Flavian Amphitheater, the Colosseum was designed for entertainment. Gladiator fights, mock sea battles, executions and plays based on Roman mythology were some of the forms of entertainment hosted in the Colosseum. The Colosseum had a seating capacity for 50,000 spectators.
  
  

Parthenon

• Completed in 432 B.C., the Parthenon is the largest temple on the Acropolis of Athens, Greece. Perikles, an ancient Athenian leader, was responsible for the building of the temple; the Parthenon replace a temple destroyed during the invasion of the Persian Empire. The Parthenon is 225-feet long and features 34-foot tall columns around the temple's colonnade area. This monument was built in honor of the ancient Greek goddess, Athena.
  
  

Arc de Triomphe

• Arc de Triomphe is a military monument in Paris, France. This arch monument is on the Champs-Elysées avenue. Arc de Triomphe was built in honor of the French soldiers who died during the French Revolution and Napoleonic Wars. Napoleon Bonaparte commissioned the monument's construction in 1806. The monument stands at 164 feet tall and is made from stone. Reliefs of French soldiers and Napoleon are on the Champs-Elysées side of the Arc.
  
  

Winter Palace

• The Winter Palace in St. Petersburg, Russia, was the formal residence of the Russian czars from 1760 to 1917. This Baroque-style palace is in the city's Palace Square. The building of the Winter Palace was completed during the reign of Catherine the Great. This monument was also the site of October Revolution, when the Bolsheviks stormed the Palace to overthrow Czar Nicholas II. Currently, the Winter Palace is part of the Hermitage Museum.
  
  

Westminster Abbey

• The Westminster Abbey is a medieval-era cathedral in the Westminster district of London, England. Built in 1245, the current Abbey church has been the coronation location of England's monarchs since its completion. Westminster Abbey is also the resting place of many of England's royalty, nobility, philosophers, artists and statesmen. This cathedral is also where English royal weddings occur.