Zemen monastery looks humble compared to Troyan or Bachkovo, and insignificant compared to Rila. It just consists of a really tiny church in a meadow. Yet it has truly beautiful medieval frescoes, the finest that survive in Bulgaria. They date back to the 1350s and were executed in the Macedonian style, unlike most of their contemporary works which harbored the more formalized Târnovo style. They have mostly a blue grayish background which enhances the ochre figures depicted. One famous scene features blacksmiths forging nails in preparation for Jesus' crucifixion.