The RIALTO and St. Mark's are two of the most popular tourist attractions in Venice, Italy. The RIALTO is a bridge that spans the Grand Canal and is one of the oldest bridges in the city. It is also a popular shopping destination. St. Mark's is a large basilica located in the heart of Venice. It is known for its ornate architecture and its many works of art. Both of these attractions are must-sees for any visitor to Venice.