How often are Tube seats washed?

Not getting a seat on the Tube may not be such a bad thing after all.

Why? An investigation by the Metro has revealed that seats on seven of the Underground lines do not get cleaned. Eww.

See also: What are the dirtiest places on a plane?

See also: Man's body undiscovered in Tube station for seven hours

Responding to a Freedom of Information request, Transport for London (TfL) told the paper that seats on the District, Jubilee, Northern, Circle, Piccadilly, Metropolitan and Hammersmith and City lines are never shampooed.

The Bakerloo, Victoria and Central line get a wash once every six months.

However, before we get too grossed out, it's important to note that TfL says carriages get a clean every night back at the depot, with seats being brushed regularly and hoovered on a 21-day rotation.

Back in 2014, Time Out magazine carried out a test to see how dirty Tube seats are, and video shows clouds of dust (thought to be a combination of human skin and dirt from shoes) billowing out after they're hit with a rubber hammer.

Testers looked at the Piccadilly, Victoria, Northern, Bakerloo, Jubilee, Central, District, Circle, Hammersmith and City, and Metropolitan lines.

At the time, the Piccadilly line seemed to have the most dust coming out of its seats.

The London Underground's Chief Operating Officer, told the Independent back in 2014: "Over four million journeys take place every day across the Underground network.

"Our trains and stations are professionally cleaned throughout the day and night."