Most buildings are built to stand up straight, but these look as if they might fall over! The Church Tower of Suurhusen Built in 1450, the 27-meter-high church tower lies in Suurhusen, Germany. It was built in wet land on foundations of oak tree trunks(树干). When the land was drained(排水) later, the wood broke down, causing one side of the tower to be a little lower than the other. In 1975, the tower became a real hazard and people were not allowed to enter until the foundations were made strong again. The lean (倾斜) of the tower is now about five degrees. The Leaning Tower of Pisa The work of building the tower began in 1173, and was finally completed in 1372. In fact, it began to lean after just a couple of floors were built. And this condition continued in the centuries after its completion. The tower was finally closed to the public in 1990 after people failed to stabilize (ii ta i) its foundations. In 2001, it was reopened after engineers removed soil from underneath its raised side. Now it leans just an angle of 3.97 degrees. Capital Gate of Abu Dhabi Completed in 2011, the Capital Gate tower in Abu Dhabi was designed to lean eighteen degrees. The building stands next to the Abu Dhabi National Exhibition Centre and contains, among other things, a fine hotel with wonderful views of the harbor. Also known as the leaning tower of Abu Dhabi, the tower is one of the tallest buildings in the city. Big Ben of London The building leans 0. 26 degrees to the northwest. This is mainly caused by the engineering projects that have been carried out in the ground below it since the late 1800s. The tower, which has been continuously open since it was completed in 1858, has nowhere near the lean of the Tower of Pisa and is still completely safe to enter.