The tunnel is 3,200 metres long and crosses the Chaîne de l'Épine on the A43 autoroute between Lyon and Chambéry.

The westbound tunnel was completed in 1974, and opened to two-way traffic at the end of 1974, the same time as the autoroute between Bourgoin-Jallieu and Chambéry.

Work had begun on the eastbound tunnel, however was delayed due to roughly 2000m² of sand and mud needing to be cleared out from the cavity.

[2] After the tunnel opened, visitors were not permitted to the cavity due to an increase in exhaust emissions.

The tunnels are straight however have a slight curve at each end, which makes it difficult to see the exit on approach.