Passage graves are ancient burial structures typically found in Neolithic cultures. They consist of a long passage leading to a central chamber, which is often covered by a mound of earth or stones. These graves were used for communal burials and are usually constructed from large stones, showcasing impressive engineering skills of early societies. The design of passage graves varies, but they often align with astronomical events, such as solstices. Notable examples include Newgrange in Ireland and Maeshowe in Scotland. These sites provide valuable insights into the rituals and beliefs of prehistoric peoples, highlighting their connection to the landscape and the cosmos.