Complex sentence: Due to the soft sandstone banks, it is difficult to build bridges that can carry road traffic; the only public road bridges are at Bridgnorth and Bewdley, meaning that there is no way for road traffic to cross the river for 25km (15 miles).
Split into simpler sentences: Due to the soft sandstone banks, it is difficult to build bridges. The only public road bridges are at Bridgnorth and Bewdley, meaning that there is no way for road traffic to cross the river for 25km (15 miles).