In 1273 the counts of Kyburg died out. Agnes of Kyburg, who had no male relations, sold the family's lands to King Rudolf I von Habsburg. He granted Aarau its city rights in 1283. In the 14th Century the city was expanded in two stages, and a second defesive wall was constructed. A deep ditch separated the city from its "suburb;" its location is today marked by a wide street named "Graben" (meaning Ditch).