 The terrain in the vicinity of Nierstein and Oppenheim was conducive to artillery support, with high ground on the west bank overlooking relatively flat land to the east.However, the same flat east bank meant that the bridgehead would have to be rapidly and powerfully reinforced and expanded beyond the river since there was no high ground for a bridgehead defense.The importance of quickly obtaining a deep bridgehead was increased by the fact that the first access to a decent road network was over inland at the town of Groß-Gerau.