This is the spiritual home of the Polish state, testifying to the strong historical link between the Polish royalty and the Catholic Church. There's been a church here since around 1000 A.D., and the present, mostly Gothic, church dates from around the mid-14th century. The chapels here and the Royal Tombs below hold the remains of all but four of Poland's 45 rulers (King Kazimierz the Great's tomb is in red marble to the right of the main altar), as well as a clutch of national heroes, including Polish and U.S. Revolutionary War hero Tadeusz Kosciuszko and Polish romantic poet Adam Mickiewicz. The most recent addition came in 2010, with the untimely death of Polish President Lech Kazcynski. Admission includes the tombs and the climb to the top of the Zygmunt Bell, which dates from the early 16th century. The bell is rung only occasionally to mark highly significant moments, such as the death of Pope John Paul II in 2005. Audio headphones are available for a nominal fee and, while the text is long and laborious, the headsets do make it much easier to negotiate the main sights.