Passage: The territory on which the offensive was to be staged was a slightly hilly plain covered with ravines and possessing significant areas of swamps and forests that restricted military movement. Its most important hills reached heights over 270 m (890 ft), allowing for improved artillery defense. In 1943, the area was for the most part covered with pine and mixed forests and thick bushes.Numerous rivers also passed through the area, the most important of them being the Donets Basin, Western Dvina, Dnieper, Desna, Volost' and Ugra rivers. Dnieper is by far the largest of them and strategically most important. The surrounding wide, swamp-like areas proved difficult to cross, especially for mechanized troops. Moreover, like many south-flowing rivers in Europe, the Dnieper's western bank, which was held by German troops, was higher and steeper than the eastern. There were very few available bridges or ferries.

Question: What height in feet did the hills reach?
890