Built on a Greek cross plan wiith five domes. this is the third church to stand on the site.. The first which enshrined the body of St Mark in the 9th century was destroyed by fire. The second pulled down to build a church reflecting Venice's power.. Inspired by the Church of the Apostles in Constantinople. 12th and 13th century mosaics cover over 45,000 sq feet of the interior. The central dome is the Ascension dome. The Pentecost Dome shows the descent f the Holy Ghost as a dove.