Sinkholes, depending on who you are, are either incredibly fascinating or slightly terrifying. These wonders of the world manage to eviscerate nearby homes, forests, mountains, and everything else unlucky enough to get caught in the mouth of the hole. However, they can also provide the country where they are located with a nice spot for tourists to explore. Some are perfect for swimming, others are just natural wonders you can take pictures of, but all of them are fascinating to some degree.
Located west of Cairo, Egypt, this massive natural sinkhole measures 80km long by 120km wide. The pit is filled with sludge, which is quite dangerous. Scientists have attempted to harness the sinkhole in an effort to obtain energy independence more recently. This particular hole, which is only one of many throughout Egypt, is completely natural.