Archaeologists surveying the ground at Liverpool Street station in preparation for Crossrail tunnelling have unearthed hundreds of skeletons on the site of a historic mental health hospital.

Opened in 1247, St Bethlehem hospital was the first institution dedicated to mental health patients and is believed to have led to the coining of the word "bedlam".

The site now lies beneath what will be Liverpool Street's new Crossrail ticket hall.

There are 20 archaeology digs along the Crossrail route and they have to be completed as part of the planning regulations.