the city was bombed in world war ii, but the bombing had little importance in the course of the war. 28.5% of the houses were destroyed and 44.7% damaged. 26.8% of the houses had no damage. the center, which still had its medieval character until then, was almost levelled. as in many cities, priority was given to rapid building of badly needed housing, and concrete structures took the place of the destroyed buildings. fortunately, most of the major churches, two of them now unesco world heritage sites, were rebuilt in the original style soon after the war. during the war, valuable world heritage materials had been hidden in the basement of the city wall. in 1978, the university of hildesheim was founded. in the 1980s a reconstruction of the historic center began. some of the new concrete buildings near the marketplace were torn down. replicas of the original buildings were built in their place.