A 20–35 km wide stretch of land in Vyborgsky District and Republic of Karelia to the west of the Vyborg–Hiitola railway, as well as the islands and shores of the Gulf of Vyborg, belongs to the strictly guarded zone of the border control, reaching the shore of Lake Ladoga at Hiitola. In 1993–2006 the zone was formally 5 km wide, although in fact it has always been much wider. Visiting it is forbidden without a permit issued by the FSB (by KGB during the time of the Soviet Union).