The Clapham Junction rail crash occurred on the morning of 12 December 1988, when a crowded British Rail passenger train crashed into the rear of another train that had stopped at a signal just south of Clapham Junction railway station in London, England, and subsequently sideswiped an empty train travelling in the opposite direction. A total of 35 people died in the collision, while 484 were injured.

Waterloo station, also known as London Waterloo, is a major central London terminus on the National Rail network in the United Kingdom, in the Waterloo area of the London Borough of Lambeth. It is connected to a London Underground station of the same name and is adjacent to Waterloo East station on the South Eastern Main Line. The station is the terminus of the South West Main Line to Weymouth via Southampton, the West of England main line to Exeter via Salisbury, the Portsmouth Direct line to Portsmouth Harbour which connects with ferry services to the Isle of Wight, and several commuter services around west and south-west London, Surrey, Hampshire and Berkshire.