Jagiellonian University’s oldest building (and one of the oldest in Kraków), Collegium Maius was built as the university’s main campus in the late 14th century, 36 years after the university’s founding. A century later it was redesigned as the late-Gothic structure surrounding the picturesque arcaded courtyard that has survived to this day. While professors lived and worked upstairs, it was in the ground floor lecture halls that Nicolaus Copernicus made doodles in the margins of his notebooks in the 1490s. Today a museum, over hour-long guided tours of the interiors and exhibits are given in English Mon-Fri at 13:00 (16/12zł), while more basic 30+ minute tours in English depart frequently (12/6zł); it is suggested, however, that you call or visit in advance to reserve yourself a place on a tour. Inside you'll visit the lecture hall, common rooms, professors’ quarters, library and treasury, seeing some fabulous interiors, paintings, furniture, medieval scientific instruments, rectors’ maces and other university memorabilia along the way, as well as the oldest surviving globe to depict the Americas. There is also a separate temporary exhibit entitled Science: Antiquated & Not-so-antiquated (rough translation; exhibit open Mon-Fri 09:00 - 14:00; Sat 09:00 - 13:00; closed Sun. Admission 7/5zł). Another highlight of visiting is the courtyard clock, from which wooden historical figures appear and parade past to music from the mid-16th century every two hours between 09:00 and 17:00. The building's courtyard also houses a gift shop and cafe, and don't miss the peaceful Professors' Garden just next door (accessible via a beautiful painted passageway from April until mid-October).