By August 1941, the Finns advanced to within 20 km of the northern suburbs of Leningrad at the 1939 Finnish-Soviet border, threatening the city from the north; they were also advancing through East Karelia, east of Lake Ladoga, and threatening the city from the east. The Finnish forces crossed the pre-Winter War border on the Karelian Isthmus by eliminating Soviet salients at Beloostrov and Kirjasalo, thus straightening the frontline so that it ran along the old border near the shores of Gulf of Finland and Lake Ladoga, and those positions closest to Leningrad still lying on the pre-Winter War border.