The tunnel on the Left Hand Side (LHS) of the Parsik Hills has been opened on both sides and is now fully tunnelled.

The Airoli Katai Naka Project is divided into three distinct segments. After the tunnelling work is over, the 3.4 km length between Thane Belapur Road and National Highway 4 would shortly be reduced to 1.69 km (under phase 1). Two tunnels, a road, and an elevated road are all part of the new section. The tunnels will have 4+4 lanes total, including 1+1 refuge lanes, per project specifications.

The New Austrian Tunneling Method (NATM), a controlled blasting technique, is being used to construct the tunnels. Currently, 67% of the tunnel's construction is finished, with the remaining 35% still ongoing.

At the moment, travellers must divert from Mahape or Thane. This project will cut the distance between Kalyan-Dombivali and Navi Mumbai by 7 km. Commuters going to Kalyan, Dombivli, Ulhasnagar, Ambernath, and Badlapur will benefit immensely from the initiative.