Interior view of choir and apse of San Giovanni Evangelista, built c.426-30 by Galla Placidia. The east apse is round on the inside and polygonal on the outside, pierced with an unusual row of seven windows. Another three openings below the windows are now closed; scholars do not agree when this happened, but some maintain it was as early as the 5th century. Sadly, some very precious mosaics that once adorned the apse have been completely lost to "renovations" in the 16th century. They included portraits of most members of the imperial family of Theodosius and two depictions of St. John the Evangelist saving Galla Placidia from the storm at sea.