The document lists several important monuments and landmarks that can be visited in Krakow, Poland, including: the Main Square, which is the largest medieval town square in Europe; Wawel Castle, originally built in the 14th century and rebuilt over time; the Krakow Barbican, one of the few remaining fortification relics that once surrounded the city; and several historic churches, such as St. Mary's Basilica and the Church of Saints Peter and Paul.