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The fortification on the right bank of the Uša was first mentioned in 1388, although it is probable it was erected even before that date. Rectangular earthworks with stone walls 3,5 metres high and 11 metres wide formed the basis of the future castles and military camps formed on that location.[1] The town itself was first mentioned the following year in a document issued by Kaributas, Prince of Severian Novgorod, who on December 16 assured his tributary fidelity to his cousin, King Jogaila and Jadwiga of Poland.