The A2 is a major road in south-east England, connecting London with the English Channel port of Dover in Kent.

It was an important route for the Romans linking London with Canterbury and the three Channel ports of Rutupiae (now Richborough), Dubris (now Dover) and Portus Lemanis (in modern Lympne).

In Anglo-Saxon times it became part of a longer road known as Wæcelinga Stræt ('Watling Street' in modern English).

The Strood to Swanscombe dualling was constructed from 1 June 1964, being seven miles, with a contract of £4,436,869 given to A. Monk Ltd of Padgate, near Warrington.

The M20 motorway to Folkestone was constructed in stages from the 1960s and provided a faster route to Dover following extensions built in the early 1990s, after which traffic levels on the M2 and A2 reduced.

It was also rerouted away from the houses of Gravesend/Singlewell to make room for the new lanes and reduce the amount of noise and pollution from the widened roads.

[9] Its original alignment roughly followed a mix of the ancient Celtic route and the turnpike road to Dover.

Shortly after here, the A2 crosses the A205 South Circular Road and becomes a motorway in all but name, with 3 lanes and a hard shoulder in each direction.

Motorists should be aware that the section between the Blackwall Tunnel Approach and Dartford Heath is monitored using average speed cameras.

Just before the A2 reaches the junction with the A2018, the speed limit increases to the national speed limit (70 mph, 112 km/h) as the road crosses the Greater London boundary to head eastwards into Kent towards Dartford, bypassing the town to the south and cutting through Dartford Heath.

The next junction links the road to the M25 London Orbital Motorway at Dartford; the next, (Bean Interchange), is for the B255 and A296 for Bluewater, where Watling Street rejoins the A2.

This latter section, from the Pepper Hill Interchange (near Northfleet and the Ebbsfleet International railway station), to the Cobham Interchange underwent extensive works (2007–2009) to move the entire carriageway south to run parallel to the Channel Tunnel Rail Link, so as to move the road away from residential housing – and continue using four lanes in each direction, with grade separated junctions.

The A278 departs from the A2 to head south to meet the M2,[11] whereas the A2 goes through Rainham and Newington before entering green country for the first time since Three Crutches.

The road meets the A249, now dualled, to the west of Sittingbourne, before going through the town itself (bypassing the now-pedestrianised High Street, as it does in Rochester and Chatham).

Leaving Sittingbourne, the A2 continues east in an almost straight line, for it is still along the alignment of Watling Street at this point.

At Ospringe it passes the Maison Dieu, now a museum of Roman artifacts but originally a wayside hospital[12] commissioned by Henry III in 1234.

It meets the A256 for Sandwich and Ramsgate at a briefly dualled section, before reverting to single carriageway for the final time.