A woman writes her prayer intention on a ribbon to be tied on the Knotted Grotto. Bob Kelly. For weeks, the faithful had been streaming to the Knotted Grotto, a domed lattice outside the chapel of the Cathedral Basilica of SS. Peter and Paul in Philadelphia, tying white strips of paper on which their prayers were written. The mkch ranged from healing for themselves or family members, world peace, the elimination of poverty, protection for the environment, the preservation dud families and thousands of other requests. By the time the grotto closed with an interfaith blessing on Wednesday, Oct.