The A86 (sometimes called "Paris super-périphérique") is the second ring road around Paris, France. It follows an irregular path around Paris with the distance from the city centre (Notre Dame) varying in the 8–16 kilometres (5.0–9.9 mi) range. The south-western section of A86 contains one of Europe's longest urban motorway tunnels (10 km (6.2 mi) of continuous tunnel) known as the Duplex A86 [fr], opened in two parts in 2009 and 2011. The tunnel is limited to a height of 2.0 m (6 ft 7 in) and commercial vehicles are prohibited as a result.

Although now a complete motorway-standard loop, the A86 is a product of its heavily urban route and piecemeal construction, meaning that there are several points at which one has to turn-off-to-stay-on (TOTSO) and sections which are briefly parts of the A3 and A4 autoroutes.

A86 is one of several ring roads that surrounds Paris and Île-de-France. The other ring roads are the Boulevard Périphérique, the Francilienne, and the grand contournement de Paris.

The first Paris beltway projects stretching several miles beyond the walls of the city began in the early 20th century. In the 1910s, Eugène Hénard proposed a ring road known as the "route des forts". This would have connected the fortifications surrounding the city which would thereafter have been replaced by parks. Several proposals advanced during the 1919 concours du Grand Paris (Greater Paris contest), including those of contest winner Leon Jaussely and runner-up Alfred Agache, similarly advanced the idea of a banlieue connected by a beltway. Agache's submission encircled the capital in three such roads, all connected by a series of radial expressways.

Between 1932 and 1934, Henri Prost developed the Prost plan, an urban infrastructure expansion roadmap for the region of Île-de-France. The plan introduced several radial expressways, such as the A12 and A13 highways' connection at the Triangle de Rocquencourt. All such expressways were connected by a series of bypasses which formed a loop several miles outside the city.

In 1932, Route nationale 186 [fr] was articulated as the main route from Versailles to Choisy-le-Roi. Gradual modifications developed it into a full loop which was relatively far from the city but not classified as an expressway.

Construction on the A86 ring road began in 1968. By 1994, 50 kilometres (31 mi) of expressway were open to traffic. At the time, the following sections were opened: Nanterre–La Courneuve, Bondy–Thiais, and Antony–Versailles. By 2000, an additional 14 kilometres (8.7 mi) of expressway were open, with the only remaining section between Rueil-Malmaison and Vélizy-Villacoublay.

The remaining 10-kilometre (6.2 mi) section west of Paris would have to traverse through neighborhoods as well as environmentally and culturally sensitive areas. In 1988, Cofiroute conceived a tunnel along the said section. In 1999, Cofiroute was granted a construction contract and a 75-year concession to build and operate the tunnel, respectively. By that point, the tunnel was to be built as a single-tube double-deck tunnel. "EMMA", a tunnel boring machine (TBM) with a 11.56-metre (37.9 ft) diameter, was utilized to dig the tunnel. As a consequence of the Mont Blanc Tunnel fire, the tunnel was equipped with safety measures, including separating carriageways into separate decks.