A team started from each end, and a third group began work on a ventilation tunnel 1.6 miles [2 km] long, which was to meet the main tunnel 4 miles [6.5 km] from the Laerdal entrance.
Divas grupas sāka strādāt katra savā galā, bet trešā grupa sāka būvēt 2 kilometrus garu ventilācijas tuneli, kam bija jāsavienojas ar galveno tuneli 6,5 kilometru attālumā no Lerdāles puses.