In the 1960s Gennady Mokeev (born 1932) formulated a different concept of the historical growth of Moscow. According to Mokeev, medieval Moscow, constrained by the natural boundaries of the Moskva and Neglinnaya Rivers, grew primarily in a north-easterly direction into the posad of Kitai-gorod and beyond. The main road connecting the Kremlin to Kitai-gorod passed through St. Frol's (Saviour's) Gate and immediately afterwards fanned out into at least two radial streets (present-day Ilyinka and Varvarka), forming the central market square. In the 14th century the city was largely contained within two balancing halves, Kremlin and Kitai-gorod, separated by a marketplace, but by the end of the century it extended further along the north-eastern axis. Two secondary hubs in the west and south spawned their own street networks, but their development lagged behind until the Time of Troubles.