The second, more northerly section is far shorter (44 km (27.3 mi)), constructed as a super two autoroute (one lane in each direction), which bypasses Rimouski to the south and ends at a roundabout junction with Highway 132 in Mont-Joli.

While the Quebec government has completed environmental and economic reviews of the impact of linking the two sections of Autoroute 20,[3] it has not committed the funds necessary for construction.

The westernmost section of A-20 was named the Autoroute du Souvenir (Remembrance Highway) in 2007 to honour Canadian veterans.

Road marker signs on this stretch of the autoroute feature a poppy (a traditional symbol of Remembrance in Canada).

A-20 then traverses the West Island (in French, l'Ouest de l'Île) along the north shore of Lac Saint-Louis to an interchange with A-520.

Commonly called the Dorval Interchange, this exit is the main access to Montreal's Trudeau International Airport.

The longest section of A-20 (from its junction with A-25 to its easternmost terminus) is named after Jean Lesage, who served as Premier of Quebec from 1960 to 1966, during the Quiet Revolution.

Autoroute Jean-Lesage currently exists as two discontinuous sections separated by about 55 kilometres: From the junction with A-25, A-20 travels east, away from the St. Lawrence River.

As it continues eastward, A-20 passes the regional centres of Montmagny and La Pocatière before approaching Rivière-du-Loup and the junction with A-85 at km 499.

Frustrated by the long delay in linking the two sections of A-20, in 2013, the Mayor of Rimouski proposed paying for the construction by tolling the autoroute.

[6] Citing predictions for an increase in ferry traffic to and from the Côte-Nord as a result of the Government of Quebec's Plan Nord, in 2011 the Mayor of Matane called for the further extension of A-20 to his city.

[7] Autoroute 20 serves as the backdrop to the popular 2002 Quebec film Québec-Montréal by Ricardo Trogi about seven twenty-something travellers driving between the two cities.

Older Anglophone Montrealers sometimes still refer to the section of the A-20 west of the city as Highway 2-20[a] (or "The Two and Twenty"), but the Route 2 designation was dropped in the mid 1970s.