One of the most important Byzantine monuments of Sfakia province is Panagia Kera at Agia Roumeli, near the exit of the gorge Samaria, at the site of a former a temple of the town Tarra (1st century AD) dedicated to Apollo.
The present church was built before the 15th century in the ruins of a small early Christian three-aisled basilica, the ruins of which are preserved at a fairly high height. The interior of the newer temple was frescoed, but has been almost completely destroyed, possibly by fire. Externally, a burial monument of the Venetian occupation in the form of an arcosolium is preserved.
The arch and the walls of the early Christian are preserved almost at their original height, with the doors being small. The sanctuary preserves a double-lobe window with a small marble pillar. In the center of the church (central and southern aisle) are preserved mosaic floors with geometric representations of the 6th century with intersecting semicircles and rooms with geometric shapes, circles, scales and strips.