It will be a 2.6 km-long tunnel on Panvel-Karjat suburban railway; currently Parsik tunnel is the longest at 1.3 km
https://www.mid-day.com/mumbai/mumbai-news/article/construction-of-longest-tunnel-on-mumbai-suburban-railway-takes-off-23272016
https://www.mid-day.com/mumbai/mumbai-news/article/construction-of-longest-tunnel-on-mumbai-suburban-railway-takes-off-23272016
Construction of longest tunnel on Mumbai suburban railway takes off
www.mid-day.comIt will be a 2.6 km-long tunnel on Panvel-Karjat suburban railway; currently Parsik tunnel is the longest at 1.3 km