Kulturnatten
culture night (http://kulturnattenuppsal...). on the second saturday of september every year, most people working in culture in uppsala show their talents downtown to masses of people walking around.
swimming
Go swimming at Fyrishov, Idrottsgatan 2, Tel. +46 18 727 49 50, (http://www.fyrishov.se/fy...).
Uppsala Reggae Festival
(http://www.uppsalareggaef...) is held for three days every summer. they have lots of international artists.
Valborg
Attend the Valborg celebrations, held on the last of April every year. (http://www.uu.se/node134) (http://planetenuppsala.se...). During the day, tens of thousands of people are out on the streets and parks. Lots of champagne is consumed or sprayed and the whole town is like one big festival. At 10AM, students riding decorated rafts race down the Fyris river, usually crashing in the two waterfalls. At 3PM, lots of people gather below Carolina Rediviva and put on their white student caps at a signal, and the masses rejoice. At 9PM, a choir is singing an ode to spring by the castle.