Marvel at the size of Sanctuary of Santa Maria delle Grazie. Stay for a mass if you can or just take a seat and enjoy a break from the outside world.
You'll have no end of sightseeing choices when staying in San Giovanni Rotondo. Sanctuary of Santa Maria delle Grazie is a great place to begin here, but there are loads of other worthy places to check out. Padre Pio Pilgrimage Church, Padre Pio Shrine, and Santuario di San Matteo are near the principal church and will round out your day nicely.