A huge crack has appeared across a road near a busy railway line where speed restrictions have already been put in place. The damage was pictured at Folkestone Warren near the tracks which run between the town and Dover. It comes after part of the nearby promenade at the beauty spot has lifted up, creating an uneven surface. The movement is believed to have been caused by heavy downpours which have saturated the ground below the concrete. As a result, a 20mph limit has been imposed on trains travelling in both directions along a 1.2 mile stretch between Abbotscliffe and Martello Tunnels “to en…