London is a city that can boast one of the oldest public transport systems in the world.

The first buses came into service in 1829 and these days more than 5 million bus journeys are made on a typical day across the London bus network.

However, in its nearly 200 years the transport system has rarely had to deal with weather as hot as we've seen in 2026.

Boiling buses

Only 500 out of the total of 9,000 London buses have full air conditioning. The rest have a combination of something called 'forced air ventilation', consisting of tinted glass, white roofs and the opening of the main windows in an effort to keep the passenger deck cool. 

But with summers like 2026 set to become more common in the years ahead, many feel these measures are insufficient to ensure a safe and comfortable ride for passengers and drivers.

The working conditions of London bus drivers during various heatwaves both in 2025 and 2026 has become an increasingly contentious issue.

It's forced some to stage strike action. 

CGTN Europe spoke to Nadine Edwards from trade union Unite which represents over 1.2 million workers, including bus drivers. She said the conditions on London buses this summer were unsafe for both passengers and drivers.

She declared: “Cabs are getting up to 45 degrees so the driver is unbelievably fatigued, very hot and and it makes it really difficult to drive, to concentrate. You We're having members report nausea, and sunstroke, so it's a really dangerous situation.”

London mayor Sadiq Khan has called on the private bus companies to have all their vehicles fitted with some form of air conditioning. But they insist the publicly owned Transport For London (TFL) should pay for it.

Going underground

It's a rather more complicated picture on the London Underground, particularly when it comes to the network's tunnels.

The world's oldest underground rail system has been running since 1863.

Its first deep-level tunnels were created by tunneling through clay. However, clay absorbs heat, and after 163 years of train travel, the system has formed a heat sink. 

So while fitting aircon on the tube may cool individual carriages, it would also produce more heat across the rest of the underground network.

CGTN Europe spoke to several tube passengers, most of whom said they had become used to the stuffy conditions underground.

One lady said: “It would be better if there was air conditioning across the different trains on the underground”

Another woman added: “I have a neck fan which really helps but without that today I'm a bit exhausted, to be honest.”

New generation of tube trains

Passengers could get some respite soon, though, with TFL set to roll out new trains later this year.

The new Piccadilly Line will become the first deep Tube line to enjoy full air conditioning.

However, that's just one of 11 lines, so the oldest underground rail network in the world still has some way to go before conditions improve for its overheated customers.

Race against time 

Meanwhile outside of London, the need to modify rail infrastructure is even more pressing in light of the climate crisis.

Two train derailments in the south of England in August caused several injuries and travel disruption. Investigators have made extreme heat the focus of their inquiries. 

It seems Britain's vast and varied public transport network is in a race against time to adapt to the challenges of global warming.