Venice is a must-see for solo travelers. It has made our list as one of the 15 Places to Visit Before They Disappear, and for good reason. The rising water levels have become a great concern and floods have become common. So before this beautiful city suffers any more damage, make sure you go and visit. Take a boat tour, visit the Rialto Market, enjoy a Gondola Ride, visit the Teatro La Fenice and the Palazzo Ducale museum.