At the end of the fourteenth century and through the first half of the fifteenth century, during the rule of Prince Lazar and his son Despot Stefan Lazarević, a great number of hesychasts found their last safe havens in Serbia. It is not widely known that many monasteries and anchoretic cells were founded in the northeastern region of Serbia, in the mountainous area of the Crnica River Gorge and further north in the Gornjak Ravine. The followers of Gregory of Sinai founded these cells; they came from both Bulgaria and Mount Athos and were known from written sources as Sinaites, albeit most had never visited Sinai. My paper will focus on hesychasts in these regions. I must inform the readers that in early 80s the monastery of Lešje was still awaiting archaeological excavations. Since then, the complex has been thoroughly rebuilt by the monks who unfortunately devastated the existing medieval remnants. Therefore today the monastery’s architecture is not authentic.