The only 2 London Underground stations where doors open on both sides of the train

The London Underground, a marvel of engineering that transports millions of passengers around the capital annually, is full of peculiarities.

With 11 lines spanning approximately 402km and serving 272 stations across the city, it's a world unto itself, both above and below ground.

Typically, when a train pulls into a station, passengers can only disembark from one side. However, the side on which the doors open varies from station to station.

In some cases, if a train terminates at a middle platform, the doors may open on both sides.

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Take for instance, the Piccadilly line, if it terminated at Arnos Grove in the middle platform; doors open on the left for those alighting and on the right for westbound travellers.

Interestingly, there are two non-terminus Tube stations where the doors open on both sides of the train - a rarity on the network. One such station is Stratford, where the doors open on both sides on the westbound Central line platforms.

At Stratford, passengers have the option to exit to the right for National Rail services or to the left for the Jubilee line, DLR and the station exit. This unique setup also gives customers the choice to wait for the westbound service on either platform 3 or platform 3a, depending on their route to the station.

Stratford's Platform 3a, which first came into use in 2010 ahead of the London 2012 Olympic and Paralympic Games, was designed by Transport for London (TfL) to facilitate easier transitions for passengers onto other lines or exiting the station. This was particularly useful when thousands of spectators flocked to the area for the Olympic Park.

Similarly, Barking station in East London also features this unique design on its eastbound District line platform, platform 2. The dual-sided door opening allows passengers to conveniently switch between London Underground trains on platform 2 and National Rail trains on platform 4.

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