Increasing traffic by other companies, including goods traffic, led to the track between King's Cross and Moorgate being widened to four tracks in 1868; the route was called the 'City Widened Lines'. Suburban services from the Midland Railway ran via Kentish Town and the Great Northern Railway ran via Kings Cross. British Rail services to Moorgate were initially steam operated before being converted to Cravens-built diesel multiple units and British Rail Class 31 locomotives class hauling non-corridor stock which remained in operation until the mid-1970s.