Blackwall Tunnel
The Blackwall Tunnel is a pair of road tunnels underneath the River Thames in east London, England, linking the London Borough of Tower Hamlets with the Royal Borough of Greenwich, and part of the A102 road. The northern portal lies just south of the East India Dock Road in Blackwall; the southern entrances are just south of The O2 on the Greenwich Peninsula. The road is managed by Transport for London.
The tunnel was originally opened as a single bore in 1897 by the Prince of Wales as a major transport project to improve commerce and trade in London's East End. It carried a mix of foot, cycle, horse-drawn and vehicular traffic. By the 1930s, capacity was becoming inadequate. A second bore opened in 1967 to relieve congestion, handling southbound traffic while the earlier 19th century tunnel handled northbound traffic.
The northern approach takes traffic from the A12 and the southern approach takes traffic from the A2, making the tunnel crossing a key link for both local and longer-distance traffic between the north and south sides of the river. It forms part of a key route into Central London from South East London and Kent and was the easternmost all-day crossing for vehicles before the opening of the Dartford Tunnel in 1963.
Until the opening of the nearby Silvertown Tunnel in April 2025, it was the easternmost free fixed road crossing of the Thames, and regularly suffered congestion, to the extent that tidal flow schemes were in place from 1978 until their controversial removal in 2007. Given the very high traffic volumes at the crossing the crossing was supplemented by the Silvertown Tunnel. When the Silvertown Tunnel opened on 7 April 2025, it and the Blackwall Tunnels were tolled.
The tunnels are no longer open to pedestrians, cyclists or other non-motorised traffic, and the northbound tunnel has a height limit. The London Buses route 108 between Lewisham and Stratford runs through the tunnels.
History
First tunnel
A tunnel in the Blackwall area was originally proposed in the 1880s. A bridge was not feasible due to shipping in the River Thames in East London. According to Robert Webster, then MP for St Pancras East, a tunnel would "be very useful to the East End of London, a district representing in trade and commerce a population greater than the combined populations of Liverpool, Manchester and Birmingham." By this time, all road bridges in London east of the ferry at Chiswick were toll-free, but these were of little use to the two fifths of London's population that lived to the east of London Bridge.The was enacted in August 1887. It provided the legal framework necessary to construct the tunnel. The initial proposal, made by Sir Joseph Bazalgette, called for three parallel tunnels, two for vehicular traffic and one for foot, with an expected completion date of works within seven years. It was originally commissioned by the Metropolitan Board of Works but, just before the contract was due to start, responsibility passed to the London County Council when the former body was abolished in 1889 and Bazalgette's work on the tunnel ended.
The original tunnel as built was designed by Sir Alexander Binnie and built by S. Pearson & Sons, between 1892 and 1897, for whom Ernest William Moir was the lead engineer. It has an external diameter of 27 feet | 8.23 metres and was constructed using a Greathead tunnelling shield and compressed air techniques. During the build they excavated a human skeleton with a stake through the middle and an elephant's tusk. It was lit by three rows of incandescent street lights. To clear the site in Greenwich, more than 600 people had to be rehoused, and a house reputedly once owned by Sir Walter Raleigh had to be demolished. The workforce was largely drawn from outside London; the tunnel lining was manufactured in Glasgow, while the manual labour came from provincial England, particularly Yorkshire.
The tunnel was formally opened by the Prince of Wales on 22 May 1897. The total cost of the tunnel was £1.4 million, and 800 men were employed in its construction, during which seven deaths were recorded.
The southern entrance gateway to the tunnel, also known as Southern Tunnel House, was designed by LCC architect Thomas Blashill and was built just before the tunnel was completed. It comprises two floors with an attic.
Today, the western bore is only used for northbound traffic and is not accessible to vehicles taller than. Given this, an expansion of the crossing had been proposed for many years—such as a third bore of the tunnel, proposed in 1989—however none of these proposals were pursued. The tunnel has several sharp bends, in order that the tunnel could align with Northumberland Wharf to the north and Ordnance Wharf to the south, and avoid a sewer underneath Bedford Street. Some sources, such as PJ Thomas, state that an additional purpose was to prevent horses from bolting once they saw daylight. The tunnel carries two lanes of traffic, though higher vehicles need to keep to the left-hand lane so that they do not hit the tunnel's inner lining.
Following the cancellation of the Thames Gateway Bridge in 2008, a new crossing from the Greenwich Peninsula to Silvertown—the Silvertown Tunnel—was proposed by TfL. Following a public inquiry, the government approved the proposal in May 2018, and the contract to build the tunnel was awarded in November 2019. Construction began in March 2021.
Second tunnel
Due to the increase in motor traffic in the early 20th century, the capacity of the original tunnel was soon perceived as inadequate. In 1930, John Mills, MP for Dartford, remarked that HGVs delivering from Essex to Kent could not practically use any crossing of the Thames downstream of the tunnel. The LCC obtained an act in 1938, the , allowing them to construct a new tunnel, but work did not start due to the outbreak of World War II. Construction eventually started in 1958 with preliminary work on the northern approach road. By this time, traffic had become progressively worse. In 1960, Richard Marsh, MP for Greenwich complained that vehicles could spend 30 to 45 minutes stuck in tunnel traffic.The new eastern tunnel, in diameter, was accepted into the roads programme in March 1959, and construction started in March 1960. It was opened on 2 August 1967 by Desmond Plummer, Leader of the Greater London Council. It is wider than the western tunnel, carries two lanes of traffic and is usable by vehicles up to in height. During construction, transport minister Ernest Marples clarified that unlike the Dartford Tunnel, also then under construction, tolls would not be imposed as the tunnel was already an established route.
At the time of opening, the strip lighting in the tunnel was commended as "a big improvement" on the standard provided in the original tunnel. In contrast with the Victorian northbound tunnel, the eastern tunnel had no sharp bends, and emergency telephones were provided. Its distinctive ventilation towers were designed in 1964 by GLC architect Terry Farrell. Immediately after opening, the old tunnel was closed for refurbishment. It re-opened on 4 April 1969 with a new overheight vehicle detection system.
In the late 1960s, proposals were made to connect the tunnel with a free-flow, grade-separated motorway system as part of the London Ringways project. The only parts of this project completed were the A102 Blackwall Tunnel approach roads in 1973.
The entrance gateway to the northbound tunnel was Grade II listed in 1973, while the ventilation towers were listed in 2000. In April 1986, the tunnel became part of the UK trunk road network. It was detrunked and control handed to TfL in September 1999.
Provisional IRA bombing
On 18 January 1979, an anonymous caller to the Press Association informed them that the Provisional IRA had planted a bomb in the tunnel that was scheduled to detonate at midnight. While the Metropolitan Police were searching the tunnel, the bomb detonated at 12:40 a.m., causing an explosion in a gas holder near the southern exit. This resulted in a fire on another gas holder approximately an hour later. No injuries were reported. Speaking in the House of Commons, Home Secretary Merlyn Rees hoped "the House will join me in condemning these attacks and will support the Government in their determination not to be swayed by such methods". A Belfast man was jailed in May 1983 for his role in the bombing, and was eventually released at the end of his sentence some 17½ years later, still professing pride in his IRA participation.Toll charges
Charging for the Blackwall Tunnel began when the Silvertown Tunnel opened on 7 April 2025. Charges for the Blackwall tunnel are the same as for the Silvertown tunnel, and apply between 06:00 and 22:00. Use of the tunnel is free overnight. Peak times are Monday to Friday, 06:00 to 10:00 northbound and 16:00 to 19:00 southbound. Users must use TfL's Auto Pay system to benefit from off-peak tolls.| Vehicle type | Peak | Off-peak |
| Cars and small vans | £4.00 | £1.50 |
| Motorcycles | £2.50 | £1.50 |
| Large vans | £6.50 | £2.50 |
| Heavy goods vehicles | £10.00 | £5.00 |
Taxis, blue badge holders, wheelchair-accessible and 'zero-emission capable' private hire vehicles licensed by TfL are exempt. Discounts are available to low income drivers in 12 boroughs, and for small businesses in Tower Hamlets, Newham and Greenwich.
In June 2025, TfL confirmed it had implemented a one month grace period for drivers who did not pay the toll charges, and that it had begun issuing penalty charges.
After the toll charges were imposed, the nearby Woolwich Free Ferry reported a daily increase in traffic of around 1,800 vehicles as drivers sought to avoid the charges.