Swayambhunath, also known as the Monkey Temple, is a sacred Buddhist site located on a hilltop in Kathmandu, Nepal. It is one of the oldest and most important Buddhist pilgrimage sites in Nepal and is also a UNESCO World Heritage Site.Swayambhunath, also known as the Monkey Temple, is a sacred Buddhist site located on a hilltop in Kathmandu, Nepal. It is one of the oldest and most important Buddhist pilgrimage sites in Nepal and is also a UNESCO World Heritage Site.