While the photos below may look like the handy work of a giant mole, the ‘Chocolate Hills’ in the Bohol province of the Philippines are actually a totally natural occurrence. The mounds are actually made from grass covered limestone and there are estimated to be between 1,260 to 1,776 separate hills in the Bohol province. The hills are believed to have been formed by hundreds of years of water erosion and they are now one of the Philippine’s biggest tourist attractions. During the dry season in the summer the hills also turn from green to a dark brown colour, which has led to their famous name: ‘The Chocolate Hills’.