Maintenance was vital for the timber bridge. It was partly burnt in the revolt led by Bajamonte Tiepolo in 1310. In 1444 it collapsed under the weight of a crowd watching a boat parade and it collapsed again in 1524.
The idea of rebuilding the bridge in stone was first proposed in 1503. Several projects were considered over the following decades. In 1551 the authorities requested proposals for the renewal of the Rialto Bridge, among other things. Plans were offered by famous architects such as Jacopo Sansovino, Palladio and Vignola, but all involved a Classical approach with several arches, which was judged inappropriate to the situation. Even the great Michelangelo was considered as designer of the bridge.
The present stone bridge, a single span designed by Antonio da Ponte, was finally completed in 1591. It is remarkably similar to the wooden bridge it succeeded. Two inclined ramps lead up to a central portico. On either side of the portico the covered ramps carry rows of shops. The engineering of the bridge was considered so audacious that architect Vincenzo Scamozzi predicted future ruin. The bridge has defied its critics to become one of the architectural icons of Venice. Source: Wikipedia