The Ville-Marie and Viger tunnels are located along route 136, formerly known as autoroute 720, along a stretch commonly referred to as autoroute Ville-Marie. The Ville-Marie tunnel was inaugurated in 1974, followed by the Viger tunnel in 1986. The project was divided into six construction lots, each subject to one or more contracts in order to optimize the sequence of interventions. The renovation work began in 2020 and will continue until 2030. The first batch of work was split into four sub-batches: the complete renovation of the exit from the Mountain, including the dismantling of the last louvers and the installation of fans (completion in progress); preparatory work for the conversion of the power supply from 12 to 25 kV (completed in autumn 2023); the replacement of 37 exhaust fans (from fall 2020 to fall 2025); and the repair of the overpasses on Saint-Laurent Boulevard and Saint-Urbain Street (from summer 2022 until the end of 2026).
