On the north side , the church of Santa Maria del Popolo is important for Raphael 's Chigi Chapel , exquisite frescoes by Pincuricchio , and , above all , two profoundly disturbing early 17th-century paintings by Caravaggio , the Conversion of St. Paul and Crucifixion of St. Peter , in the Cerasi Chapel left of the choir .
The frescoes by Pincuricchio were constructed before the Chigi Chapel .