Könchogsum Lhakhang, also known as Tsilung, is a small Buddhist monastery on the northern side of the Chokhor Valley, founded by the Tibetan prince Tsangma in the 9th century. It is one of the oldest religious buildings in Bhutan and holds significant historical importance as a link between the early spread of Buddhism in Tibet and its establishment in Bhutan.
The monastery is modest in scale — a single main temple with a small courtyard — but the age of the site and the quality of the internal murals make it a worthwhile stop for those interested in Bhutanese religious history. It is easily combined with visits to Kurjey Lhakhang and Tamshing, which are nearby in the same valley.