The chapel of Osia Melou lies to the SW of the Asclepieion, 150m west of the therapeutic spring of Kokkinonero, and is a monument dating most probably from the Byzantine period, although the existing structure was built in 1948. The German archaeologist Herzog who visited the church in 1933, believed it was the first church to have been built in Kos during Christian times. The church of Osia Melou took its name from Osia Melani (Saint Melania the Younger) or from Mello-ous/Meli (honey).
The sanctuary and the marble lintel of the ancient monument, built on a rock embedded in the ground, are still visible. Traces of murals are also discernible in the parts of the old church.