Metro 3 is a 33.5-km-long underground corridor running along Colaba-Bandra-SEEPZ.
Length of the corridor is marked with 27 stations out of which 26 will be underground.
Officials in the Chief Minister's Office said Fadnavis started his visit from Azad Maidan in South Mumbai at 11.45 PM and will tour the entire stretch till Seepz in Andheri.