Two MPs found themselves locked in the House of Commons Library on Wednesday, having stayed there working late.

BBC: Two MPs locked in Commons library after working late

It is also the most expensive public transportation in the world, according to research compiled by the House of Commons library, but it does have one of the best-designed maps in transit history.

BBC: Living in: Great cities for public transport

Researchers at the House of Commons library had concluded that "in England and Wales increases in prison population have tended to occur at a similar time to falls in levels of recorded crime", he added.

BBC: Minister rebuts MPs' claim on effectiveness of prison