Through the open window the Riva degli Schiavoni and the Campanile (bell tower) of he St Mark's Basilica can be seen. The campanile is represented with a temporary flat-roofed bell-chamber, which was in place from 1489 to 1511. The attribution to Giorgione is not universally accepted, some scholars attribute the painting to a painter close to Giorgione. (http://www.wga.hu/html_m/g/giorgion/religion/reading.html)