The Burj Khalifa has a height of 828 meters and is both the tallest building in the world and the tallest free-standing structure in the world.

Tokyo Skytree is a broadcasting, restaurant, and observation tower in Sumida, Tokyo, Japan. It became the tallest structure in Japan in 2010 and reached its full height of 634.0 metres.

The Colosseum could accommodate 50,000 spectators. It's the largest amphitheater built by the Roman empire. It's estimated that the outer wall, which is 189 meters long and 156 meters wide, was originally built using 100,000 cubic meters of travertine stone.

The Confederation Bridge is a bridge spanning the Abegweit Passage of Northumberland Strait, linking Prince Edward Island with mainland New Brunswick, Canada.

The Eiffel Tower is an iron lattice tower located on the Champ de Mars in Paris, named after the engineer Gustave Eiffel, whose company designed and built the tower.

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the opening of the San Francisco Bay into the Pacific Ocean.

The Grand Canyon Skywalk is a transparent horseshoe-shaped cantilever bridge and tourist attraction in Arizona near the Colorado River on the edge of a side canyon in the Grand Canyon West area of the main canyon.

The Great Pyramid was the tallest man-made structure in the world for more than 3,800 years. The builders responsible for the Great Pyramid of Giza would have needed more than a few tea breaks to keep them motivated. The pyramid consists of 2.3 million stone blocks.

The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east-to-west line across the historical northern borders of China in part to protect the Chinese Empire or its prototypical states against intrusions by various nomadic groups or military incursions by various warlike peoples or forces.

Hoover Dam, once known as Boulder Dam, is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the US states of Arizona and Nevada.

The International Space Station cost $100 billion to build and involved 100,000 people in 15 nations. It also ranks as one of the more unusual construction sites, located 354 kilometers (220 miles) above Earth.

Kansai International Airport was the first airport to be built on an artificial island. Construction of the island, which measures four kilometers (2.5 miles) by 2.5 kilometers (1.6 miles) took three years.

The London Underground is a public rapid transit system serving a large part of Greater London and parts of the counties of Buckinghamshire, Hertfordshire and Essex.

The Millau Viaduct has the highest road bridge deck in Europe -- it sits 270 meters (890 feet) above the Tarn river at its highest point. The Millau Viaduct is the world's tallest bridge, with a total height of 343 meters (886 ft), making it taller than the Eiffel Tower.

The Palm Islands are an artificial archipelago in Dubai, United Arab Emirates, off the coast in the Persian Gulf. Major commercial and residential infrastructure will be constructed by Nakheel Properties, a property developer in the UAE.

The Panama Canal is a 77.1-kilometre ship canal in Panama that connects the Atlantic Ocean to the Pacific Ocean. The canal cuts across the Isthmus of Panama and is a key conduit for international maritime trade.

The Aqueduct of Segovia is a Roman aqueduct and one of the most significant and best-preserved ancient monuments left on the Iberian Peninsula.

The Shanghai World Financial Center is a supertall skyscraper located in the Pudong district of Shanghai, China. It was designed by Kohn Pedersen Fox and developed by the Japanese Mori Building Company.

Taipei 101, formerly known as the Taipei World Financial Center, is a landmark skyscraper located in Xinyi District, Taipei, Taiwan.

The Taj Mahal is a white marble mausoleum located in Agra, Uttar Pradesh, India. It was built by Mughal emperor Shah Jahan in memory of his third wife, Mumtaz Mahal.

Teotihuacan also written Teotihuacán, was a pre-Columbian Mesoamerican city located in the Basin of Mexico, 30 miles (48 km) northeast of modern day Mexico City, which is today known as the site of many of the most architecturally significant Mesoamerican pyramids built in the pre-Columbian Americas.

The CN Tower was built to withstand an earthquake of 8.5 on the Richter scale. It was the world's tallest building when it was completed in 1976 and designed to withstand winds of up to 418 kph (260 mph). But strong winds and earthqua

The White Pass and Yukon Route is a Canadian and U.S. Class II 3 ft (914 mm) narrow gauge railroad linking the port of Skagway, Alaska, with Whitehorse, the capital of Yukon. An isolated system, it has no direct connection to any other railroad.