From Pressburg, the Hungarian envoys escorted the crusaders to Esztergom, where King Béla III of Hungary greeted them on 4 June. He provided boats, wine, bread and barley to the army. Frederick stayed in Esztergom for four days. The king of Hungary accompanied the army to the Byzantine border at Belgrade. There were incidents during the crossing of the Drava and Tisza rivers, but the Sava was crossed on 28 June without incident. In Belgrade, Frederick staged a tournament, held a court, conducted a census of the army and wrote to the Byzantine emperor Isaac II to inform him that he had entered Byzantine territory.