The site which originally housed St. Francis' hut was transformed into a chapel on the wish of St. Bonaventure of Bagnoregio around 1260. It was extended to its present size - forming the present day Chapel of the Roses - by St. Bernardine of Siena around 1440. It is known also as "St. Francis' cell".

The inside of the little oratorio, divided into two rooms on different levels, was adorned in the 1500s with frescoes by Tiberio di Diotallevi di San Francesco, known as Tiberio d'Assisi.
The paintings on the lower level reproduce the five images of the Altar Screen of Prete Ilario da Viterbo located in the Porziuncola, whilst those on the upper level depict St. Francis and his first twelve companions and some Franciscan saints including St. Clare, St. Bonaventure and St. Bernardine.

Under the chapel there is a cave like aperture, inside of which there is a statue of the saint in prayer and the remains of the beams which formed the pulpit on which he announced the great Indulgence of the Porziuncola.