A high-speed train rear-ends another on a viaduct on the Yongtaiwen railway line in Wenzhou, Zhejiang province, China, resulting in 40 deaths.

High-speed rail (HSR) is a type of rail transport network utilising trains that run significantly faster than those of traditional rail, using an integrated system of specialised rolling stock and dedicated tracks. While there is no single definition or standard that applies worldwide, lines built to handle speeds of at least 250 km/h (155 mph) or upgraded lines of at least 200 km/h (125 mph) are generally considered to be high-speed.

A rear-end collision, often called rear-ending or, in the UK, a shunt, occurs when a forward-moving vehicle crashes into the back of another vehicle in front of it. Similarly, rear-end rail collisions occur when a train runs into the end of a preceding train on the same track. Common factors contributing to rear-end collisions include driver inattention or distraction, tailgating, panic stops, brake checking and reduced traction due to wet weather or worn pavement.

The Wenzhou train collision was a railway accident that occurred on 23 July 2011, when a high-speed train travelling on the Yong-Tai-Wen railway line collided into the rear of another stationary train on a viaduct in Lucheng District, Wenzhou, Zhejiang province, China. The two trains derailed, and four carriages fell off the viaduct. 40 people were killed, and at least 192 were injured, 12 severely. This disaster was caused by both defects in railway signal design and poor management by the railway company.

The Ningbo–Taizhou–Wenzhou railway or Yong-Tai-Wen railway is a dual-track, electrified, high-speed rail line in Zhejiang Province, China. It is named after the three prefecture-level cities along route: Ningbo, whose abbreviated Chinese name is Yong, Taizhou and Wenzhou. The line has a total length of 282.4 kilometres (175.5 mi) and forms part of Hangzhou–Fuzhou–Shenzhen railway. Construction began in October 2005, and the line opened to commercial service on September 28, 2009. Trains running on the line reach top speeds of 250 kilometres per hour, and the shortest trip between Ningbo and Wenzhou takes 1 hour 12 minutes.