 In 1952 a rear-end collision took place at Bridgeton Cross; a train stalled in the section and a signalman thought the train had passed and that the Lock-and-Block apparatus had failed; he improperly released the lock and signalled a following train through.For much of its route the line was in a shallow cut-and-cover tunnel, and gradients were imposed by the road levels.Glasgow Central station was in a dip to enable the footbridge between platforms to cross the line, below the main station above.