Snow on the Great Wall, China

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Step up your game. The Great Wall of China

Think the Great Wall of China is just a long wall? Think again. It is a combination of walls and steep trenches that have protected China for centuries. One of the longest manmade structures in the world, this wall stretches over 20,900 kilometres and dates back thousands of years. Back then, glutinous rice flour was used to bind the bricks of the wall. The ancient marvel depicted in today's picture consists of a series of fortifications that span rugged mountains, valleys and deserts. Featuring watchtowers and garrison stations, some sections were designed to keep invaders at bay. This wall was designated a UNESCO World Heritage Site in 1987. Hiking offers a unique glimpse of this historical landmark. The experience ranges from well-preserved sections, like Mutianyu, to wild, unrestored parts such as Jiankou. Some steps are so high they feel more like climbing a ladder!