Other historical records observe other bridges, like in 1521, 1595 or 1717, but they were all temporary, pontoon bridges, constructed solely for the purpose of conquering the city during the numerous battles and sieges of Belgrade in history.
[1] The bridge was constructed further to the south from the city, near the village of Ostružnica on Šumadija side of the river.
As the Syrmian side across the Sava was a vast marsh at the time (modern New Belgrade), the bridge didn't stop at the bank but continued for some length above the swamp.
According to the records, a seasoned Belgrade master craftsman Đorđević "in only one month, with the help of his 400 workers, built the Long Bridge, using 2,000 tree trunks, 1,100 wooden piles, 15,500 bundles of palings and 12,000 palisade pickets.
[1] Maps show another pontoon bridge, on the boats, directly connecting the road from Zemun to the Belgrade Fortress.