The Shrewsbury to Chester Line, also known as the Severn–Dee Mainline (after the rivers on which Shrewsbury and Chester stand), was built in 1846 as the Shrewsbury and Chester Railway. The engineer for the line was Henry Robertson, a partner in locomotive builders Beyer Peacock, while the contractor was Thomas Brassey in partnership with William Mackenzie and Robert Stephenson.The line runs from Shrewsbury in England to Chester, also in England.