The Road Tunnels Under the Thames

Published 9 November 2026 · By the Guide to London editorial team · Editor: Terje Moy

Three road tunnels cross under the Thames in east London: Rotherhithe, Blackwall and Silvertown. Drivers pay a charge at Blackwall and Silvertown between 06:00 and 22:00, but not at Rotherhithe. You may not walk or cycle through Blackwall or Silvertown, and the only way across for a pedestrian without a vehicle is a bus, the foot tunnels at Greenwich and Woolwich, or a boat.

Most visitors never drive in London, so for them these tunnels matter in two ways. Several bus routes use them, which makes the bus the cheapest way between the Greenwich Peninsula and Canary Wharf, Stratford or London City Airport. And a hire-car driver heading for Greenwich or Kent from north London will be steered into one of them by the satnav, often without knowing it carries a charge.

The crossings that are free for walkers, the foot tunnels, the Woolwich Ferry and the cycle shuttle, have their own guide to getting across the Thames for nothing. This page is about the road tunnels themselves.

Three tunnels, three centuries of traffic

The tunnels sit close together on a stretch of river where there is no bridge at all. Tower Bridge is the last road bridge going downstream, and the next one is the Queen Elizabeth II Bridge at Dartford, outside London. Everything in between goes under the water or on the Woolwich Ferry.

The oldest is the northbound bore of the Blackwall Tunnel, opened in 1897 for the London County Council. Its granite northern portal on Poplar High Street and the sandstone gatehouse at the southern end are both listed at Grade II, and Historic England's entry for the gatehouse names Thomas Blashill as its architect. A second bore was added in the 1960s to take southbound traffic. Its two ventilation towers, with their sprayed concrete shell roofs, were designed by the London County Council's architects, and the listing records Terry Farrell as the job architect.

The Rotherhithe Tunnel followed in 1908. TfL says it was built for horse-drawn carriages and pedestrians, which explains why it is so narrow today. The Silvertown Tunnel is the newcomer, opened on 7 April 2025 a short distance east of Blackwall, mainly to relieve the queues there.

The Blackwall Tunnel: the old bore and its 4-metre limit

Blackwall carries the A102 between the A12 at Poplar and the Greenwich Peninsula, and it has long been one of the most congested roads in London. The two bores are different tunnels. The northbound one is the Victorian original, with tight bends and a height limit of 4 metres; the southbound one is wider and straighter and allows 4.72 metres.

That difference matters if you hire a large van or a motorhome. A vehicle that fits going south may not fit coming back. TfL's list of river crossing restrictions gives the limits, and it also bans abnormal loads and any vehicle carrying dangerous goods from both Blackwall and Silvertown.

For a visitor the useful thing about Blackwall is bus route 108, which runs from Lewisham through Blackheath to North Greenwich, then under the river to Poplar, Bow and Stratford. It is the slow but cheap way from the O2 to the Olympic Park, and our guide to getting to the O2 has the faster alternatives.

The Silvertown Tunnel and the buses it brought

The Silvertown Tunnel links the eastern side of the Greenwich Peninsula with the A1026 Lower Lea Crossing, the A13 and the Royal Docks. It has a dedicated lane in each direction for buses, coaches and lorries, and TfL says this lets double-deck buses cross the river east of Tower Bridge for the first time.

Two bus routes use it. Route 129 runs from Lewisham through Greenwich town centre and North Greenwich, under the river to West Silvertown and Pontoon Dock, past London City Airport and on to Beckton and Gallions Reach. The Superloop route SL4 links Grove Park, Lee and Blackheath with Canary Wharf, using the tunnel between Shooters Hill Road and Leamouth. TfL counts 21 buses an hour through the two tunnels at peak times on weekdays.

Route 129 is the one worth knowing. From Greenwich to London City Airport it is a single bus ride at the ordinary flat fare, which since 1 November 2026 has been £1.85, with no change of train. Our guide to London City Airport compares it with the DLR, and the Superloop routes have their own page.

The Rotherhithe Tunnel: free, narrow and not for vans

The Rotherhithe Tunnel runs from Limehouse on the north bank to Rotherhithe on the south. It costs nothing to drive through, but it is the most restricted crossing in London. TfL bans any vehicle more than 2 metres high or wide, or heavier than 2 tonnes, so most vans and every bus are kept out. In 2018 TfL said up to 6,500 vehicles a day were breaking the width rule.

Inside it is an old, low, curving tube with heavy traffic and very little room. TfL describes it as carrying cyclists and pedestrians as well as more than 30,000 vehicles a day, and there are narrow raised footways on each side. In other words, walking and cycling through it is not forbidden in the way it is at Blackwall and Silvertown.

That does not make it a good idea. In our view nobody should choose to walk the Rotherhithe Tunnel: you are breathing traffic fumes for well over a kilometre, a few feet from passing cars. TfL's own figures put the tunnel at 4,860 feet long. The Uber Boat RB4 ferry between Rotherhithe and Canary Wharf does the same job in a few minutes, and our page on Wapping and Rotherhithe explains what is on each side.

How the charge works, and why Auto Pay matters

Since the Silvertown Tunnel opened, both it and Blackwall have been charged. You pay for every crossing, in both directions, from 06:00 to 22:00 every day except Christmas Day, bank holidays included. Crossings between 22:00 and 06:00 are free. There are no barriers or toll booths, and you cannot pay at the tunnel: cameras read the number plate.

The price depends on two things: the time and the way you pay. TfL charges a peak rate from 06:00 to 10:00 northbound and 16:00 to 19:00 southbound on weekdays, and an off-peak rate the rest of the charging day. But the off-peak rate exists only for vehicles registered with TfL's Auto Pay. If you pay online or by phone, you pay the peak rate at every charging hour.

Charges per crossing, as published by TfL since the increase of 21 September 2026 (checked November 2026). For a visitor driving a hire car from north London to Greenwich and back on a Saturday afternoon, the arithmetic is simple. Without Auto Pay the round trip costs £8.40; with it, £3.10. Either way you have until midnight on the third day after the crossing to pay.

Miss that deadline and TfL can send a Penalty Charge Notice of £180, reduced to £90 if paid within 14 days. Non-UK vehicles can be fined too. With a hire car the notice usually goes to the rental company first, which will usually pass it on, often with an administration fee of its own. Our guide to driving in the UK as a visitor covers hire-car paperwork, and the Congestion Charge and ULEZ page covers the two other London charges, which TfL lets you pay in the same transaction.

Who does not pay

TfL-licensed black cabs are exempt, so a taxi through Blackwall or Silvertown costs you only the meter. Buses, coaches and minibuses registered with the DVLA are exempt too, and foreign-registered buses and coaches can register to avoid the charge. Zero-emission-capable and wheelchair-accessible private hire vehicles licensed by TfL are not charged while they are on a booking.

Blue Badge holders can apply for a 100% discount, but it has to be registered with TfL in advance, and TfL asks for at least ten days to process discount applications. A visitor with a disability parking permit from another country should not assume it counts.

Walking and cycling: what is banned and what replaces it

TfL states plainly that cycling and walking through the Silvertown and Blackwall tunnels is not permitted. If you are on foot, the alternatives are the two foot tunnels. The Greenwich Foot Tunnel runs from Island Gardens on the Isle of Dogs to the Cutty Sark, and the Woolwich Foot Tunnel runs beside the Woolwich Ferry further east. Both are free, and our pages give their hours and lifts.

With a bicycle, TfL runs a free shuttle bus through the Silvertown Tunnel between Seagull Lane in the Royal Docks and Millennium Way on the peninsula. TfL says it runs five times an hour from 06:30 to 21:30, every day except Christmas Day, and will operate until at least 2028. The rules on who may board are in our page on taking a bike on London transport.

The London Cable Car crosses the same stretch of river in the air, between the peninsula and the Royal Docks. It is not free and not capped, but it is the most enjoyable way over; our guide to the cable car has the fare and the hours.

The tunnels under the Thames that are not for cars

Road tunnels are only part of what lies under this river. The first tunnel ever dug under a navigable river, Marc and Isambard Kingdom Brunel's Thames Tunnel of 1843, was built for pedestrians and now carries the Overground's Windrush line between Wapping and Rotherhithe; the story is told at the Brunel Museum. Further upstream, the Tower Subway beside the Tower of London once carried a cable railway and then foot passengers, and our page on London's lost tunnels covers it.

Beyond London, the Dartford Crossing on the M25 has its own separate charge, the Dart Charge, run by National Highways rather than TfL. It is paid on the official GOV.UK Dart Charge page, and a TfL account does not cover it.

Closures, queues and what to expect at night

All three tunnels are open 24 hours a day except during planned maintenance, and the maintenance usually happens at night and at weekends. TfL says one purpose of the Silvertown Tunnel is to give drivers an alternative when Blackwall is closed for repairs, so check TfL's traffic status page before a late drive.

The peak queues follow the charge pattern. Northbound traffic builds on weekday mornings and southbound in the late afternoon, which is exactly when the peak rate applies. A visitor with a choice should cross in the middle of the day, at the weekend, or after 22:00, when it is both quicker and free. Our page on parking in London explains why most visitors are better off leaving the car on the edge of the city.

Frequently asked questions

Is the Rotherhithe Tunnel free to drive through?

Yes. The Rotherhithe Tunnel has no charge at any time, unlike Blackwall and Silvertown. It does, however, ban vehicles over 2 metres high or wide or over 2 tonnes, so it is closed to most vans and to all buses and lorries.

Can you walk through the Blackwall Tunnel?

No. TfL does not permit walking or cycling through either the Blackwall or the Silvertown tunnel. On foot, use the Greenwich or Woolwich foot tunnels; with a bicycle, use TfL's free cycle shuttle through the Silvertown Tunnel, or take a bus such as route 108 or 129.

How much is the Blackwall Tunnel charge for a car?

For a car or small van it is £1.55 off-peak and £4.20 at peak with TfL's Auto Pay, or £4.20 at any charging hour if you pay online or by phone (rates since 21 September 2026). The charge applies from 06:00 to 22:00, in both directions, and the same rates cover the Silvertown Tunnel.

Do I have to pay the Silvertown Tunnel charge in a hire car?

Yes, unless the car is exempt, and it is the driver's job to pay. You have until midnight on the third day after crossing. If nobody pays, the Penalty Charge Notice of £180 goes to the registered keeper, which for a hire car is the rental company, and it will normally pass the cost on to you.

Which buses go through the Silvertown Tunnel?

Route 129, between Lewisham, Greenwich, North Greenwich, London City Airport and Gallions Reach, and the Superloop route SL4, between Grove Park and Canary Wharf. Route 108 between Lewisham and Stratford uses the Blackwall Tunnel instead.

Sources

• Transport for London - Paying the Blackwall and Silvertown tunnels charge (checked November 2026)
• Transport for London - Silvertown Tunnel (checked November 2026)
• Transport for London - Penalty charges for Blackwall and Silvertown tunnels (checked November 2026)
• Transport for London - River crossing restrictions in central London (checked November 2026)
• Transport for London - Rotherhithe Tunnel celebrates 110 years (press release, 2018) (checked November 2026)
• Historic England - Southern gatehouse to the Blackwall Tunnel, list entry 1212100 (checked November 2026)
• Historic England - Southern ventilation shaft to the Blackwall Tunnel southbound, list entry 1246736 (checked November 2026)
• Transport for London - Route 129 stop sequence (open data) (checked November 2026)