Russian experts have started the restoration of a tunnel at the mountainous Salang pass in Afghanistan. They have begun clearing the most damaged southern entrance of the tunnel, the Russian Emergencies Ministry's humanitarian centre in Kabul told a RIA Novosti correspondent. A group of Russian experts to be involved in the construction and restoration works is expected to come soon. The tunnel at Salang pass is located at a height of 3,000 metres and its length is 2,700 metres. The tunnel was constructed by Soviet experts in 1965. In 1998 the Northern Alliance troops exploded the tunnel in order not to let the Taliban penetrate into northern Afghan provinces. The highway via Salang pass is the safest and shortest way linking Afghanistan's north with the country's central and southern regions.