Why did kiev become one of russia's greatest urban centers?

Because Kiev is known as the capital and biggest city of Ukraine, divided into two parts by the Dnieper River and popularly known for its spiritual architecture, nonreligious tombstones and olden times museums. In the 11th century, Kiev is a convent and pilgrim’s journey site surrounding numerous gold-vaulted churches. It's known for its underground cemetery consisting of a subterranean gallery with recesses for tombs bordered with the burial auditorium of traditional friars, and a gathering of gold stuffs from the prehistoric Scythian era. Kiev was originated and founded by four siblings namely; Kyi, Shchek, Khoryy, and Lybid.