Abbey of Santa Maria di Grottaferrata
Grottaferrata has preserved its abbey, founded in the 11C by Greek monks. The second courtyard is home to Santa Maria church, which sports a fine 12C Romanesque bell tower. The interior, remodelled in the 18C, reveals a triumphal arch adorned with a huge Byzantine mosaic (late 12C) depicting the apostles at Whitsun. The right-hand side nave leads into St Nil chapel, rich in frescoes (1608-10) by Domenichino illustrating episodes of the saint's life.