Almost on axis with the entrance door is a flat-bottomed niche closed at the top by a round arch and raised upper profile, supported by half-columns with a truncated-pyramidal capital and ‘book-like’ pulvinus.
This niche, dug into the rock and placed in a privileged position, houses the painting of the Archangel Michael, protector of the grotto.
At the sides are seats carved out of the rocky bank.
The arch is decorated with red flowers on a yellow background, surrounded by a large red frame between two smaller white ones.
The niche retains traces of a very damaged, single-layer painting surrounded by a red, white and black band.
It is possible to recognise the image of the Archangel Michael in a frontal position, with open wings, the globe in his left hand and in his right hand the spear piercing the mouth of the dragon.
Of the head, which has been almost completely lost, the right part of the halo, made with a compass, and traces of the hair remain.
His left arm is raised, his hand gripping a lance that vertically thrusts into the mouth of the dog-headed, serpentine-bodied dragon.
The niche was deliberately carved to accommodate the painting of the Archangel Michael, protector of the cave, and placed in a privileged position for pilgrims.
The iconography of the Archangel Michael with a central posture piercing the dragon is carved on a tile incorporated in the masonry of the cave-church of the sanctuary of St. Michael the Archangel in Monte Sant’Angelo, dated to the late 11th – early 12th century, and constitutes a model that with very few variations continued until the 13th – first half of the 14th century.