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It can get extremely warm on the Underground (Picture: AFP)The hot weather looks set to continue into the summer, with the heatwave warming up London \u2013 and the high temperatures set to continue in the coming days.
\nMask-wearing is still mandatory, so if you\u2019re enjoying a day out in the city or just commuting to work, the Tube is going to feel extra sweaty.
\nWith many Tube lines totally free from air-conditioning, you won\u2019t be surprised to hear it could reach sweltering temperatures.
\nBut which underground lines should you try to avoid on hot days?
\nWhat are the hottest underground lines?
\nThe crowded Central Line is often slammed as the hottest on the network but it\u2019s actually the Bakerloo that could be the most sweltering.
\nIn 2019, thermal imaging company Flier predicted the Bakerloo could max out at 42\u00b0C, as it more than lives up to its name.<\/p>\n
The DLR, Victoria and Jubilee lines are ofter cooler (Picture: Transport for London)If you\u2019re looking for something a bit cooler \u2013 and happen to be in south-east London \u2013 try the DLR, which is often less warm.
\n40% of the TfL network has air conditioning, and there\u2019s enhanced ventilation on the Victoria and Jubilee lines.
\nSticking to buses might be wise, too. With reflective roofs and opening windows, they can feel a lot cooler than their underground counterparts.
\nThe zero-emission vehicles generate less heat, making it a more pleasant journey.
\nWhy is the Central Line so hot?
\nThe Central Line is one of the hottest tube lines because of its age and depth beneath the ground.<\/p>\n
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It is one of the oldest lines in London and was opened as The Central Railway in 1900 with early extensions carried out in 1920 and in the 1940s.
\nThe line is a deep-level tube which means it is at least 20 metres underground and travels through two small tunnels to reach each station.
\nThis compact space and lack of ventilation means the heat generated isn\u2019t able to disperse and therefore it stays contained.
\nThe old design of the tunnels makes it difficult to create enough extra ventilation to have a big effect.<\/p>\n
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