This neolithic stone burial chamber is known as the Tomb of the Eagles thanks to the bones of hundreds of sea birds found on the spot. Now visitors can crawl inside the burial site thanks to a little board on wheels. 

The ancient tomb was first discovered in 1958, when Orkney farmer Ronnie Simison was digging around on the edge of his land for flagstones. During his search, Simison stumbled upon a chamber full of human skulls and ancient artifacts. Proper archeological excavations took place in 1976, and the remains of up to 14 white-tailed sea eagles were found alongside nearly 16,000 human bones. While the site is technically called the Isbister Chambered Cairn, thanks to the abundance of eagle bones found on the site, it is now more commonly referred to as the Tomb of the Eagles.

Carbon dating showed that the human remains hailed from a far older age than the eagle bones, which proved to researchers that the burial mound had been in use by multiple generations of people at the site. The true importance of the eagle to the creators of the tomb is unknown, but the discovery of the Tomb of the Eagles proves that they served some kind of important role in the ancient culture.

Today, visitors to the site can enter the ancient mound through a passage, but it is a cramped little shaft that it would be difficult for an adult to crawl through. To enter the tomb, guests lie down on a board mounted with wheels and pull themselves through the passage via a rope. Claustrophobes may want to skip this one.  

Update as of October 2020: Tomb of the eagle will reopen in 2021.