Untold Truth Around The world

Top secret(s): the truths behind the world's great wonders 

Ever visit an incredible site in some exotic land and wonder how it was built? The notice board just lists a few meaningless dates, or a guide rattles off a bunch of jargon-packed phrases, but you want the real dirt. Here we reveal the ingenious engineering behind 10 of the world's most epic structures – and the little-known facts that lie hidden in their depths.

1. Taj Mahal, Agra, India

 

Legend has it that Mughal ruler Shah Jahan ordered the hands of the Taj Mahal builders to be chopped off after it was completed, to prevent them from ever building anything so beautiful again - although no written evidence supports this story. The elegance of the mausoleum can be attributed to clever engineering. To make the Taj Mahal appear perfectly straight from ground level, the architect designed the minarets to slant slightly outward, which also ensured that in the event of an earthquake they would fall away from the mausoleum's precious dome.
Make the trip: get to Agra by train from Delhi (about 2 hours). Entry numbers are limited, so buy tickets the day before at the Archaeological Survey India office, known as the Taj Mahal Office by rickshaw drivers (www.asi.nic.in). The Taj Mahal is closed on Fridays.

2. Burj Khalifa, Dubai, UAE

 

This ethereal tower in the Arabian Desert cost US$1.5 billion to construct. At 828m, 2.5 times higher than the Eiffel Tower, the Burj Khalifa is the world's tallest building. To withstand high winds and earthquakes, this superscraper is designed with a 'buttressed core' – three wings set at 120 degrees to each other, anchored around a central hub. Each wing supports the others, so when the wind blows on two of the wings, the third resists the force.
Make the trip: the Burj Khalifa is in downtown Dubai. Purchase observation deck tickets at the office on the lower ground of the Dubai

3. Moai, Easter Island (Rapa Nui), Polynesia

The moai are one of Rapa Nui's most enduring images. Image by Volanthevist / Flickr  / Getty Images.

These ancient statues (among other theories) have been blamed for the demise of the Easter islanders. Transporting them on logs would have devastated forests, and without trees the soil would have washed away, causing failed harvests, famine, war and cannibalism. But satellite images of Easter Island, taken in 2005, show dirt tracks radiating from the quarry where these mysterious 10m-tall statues were carved. After attaching ropes to the head of the moai, small teams could have moved the statues by 'walking' them along.
Make the trip: LAN Airlines (www.lan.com) is the only airline serving Rapa Nui. Flights are often overbooked, so reconfirm your ticket two days before departure.

4. Stonehenge, England