A magnificent example of prehistoric architecture, Maeshowe is one of the finest Neolithic buildings and chambered cairns in Europe. This otherworldly chambered tomb may look like an eye-catching mound of grass from the outside, but like all of Orkney’s historic sites, inside awaits a maze of information. With its one-metre-wide entry, Maeshowe was made from an assortment of small and gigantic stones over 5,000 years ago. The entrance is aligned with the setting of the midwinter sun, which causes ethereal rays to illuminate the tomb’s chamber and the Barnhouse Standing Stone each year. During the 12th century, Viking crusaders sought shelter from a storm and broke into Maeshowe, where they carved Norse graffiti runes on the walls.