In the tradition of the constitution of the Reich Town ('Great Proclamation of Oath') of 1397, the Mayor of the City of Ulm appears on the balcony of the Schwörhaus (Oath House) on the last but one Monday in July and swears an oath to uphold the town constitution.

At about 11:00 h, in a speech lasting about 1 hour, he presents his account of the past year and delivers a prognosis of the political and social situation for the coming year. At the end of his speech, to the sound of the Oath bell, he promises unconditionally to serve rich and poor equally in all equal, common and honest dealings.

In the afternoon, following the traditional oath celebration in the Weinhof – by the way, all the shops in Ulm are closed- the 'Nabada', a sort of carnevalesque river procession, takes place on the Danube (by the way, 'Nabada' means 'swim down' the Danube).