The British Rail Class 717 Desiro City is an electric multiple unit passenger train built by Siemens Mobility, currently operated by Govia Thameslink Railway on its Great Northern Hertford Loop and Welwyn stopping routes. Built to replace Class 313 trains on services into Moorgate, a total of 25 six-car units began entering regular service from March 2019. The units are similar to the Class 700s and the Class 707s

Siemens Mobility is a division of Siemens. With its global headquarters in Munich, Siemens Mobility has four core business units: Mobility Management, dedicated to rail technology and intelligent traffic systems, Railway Electrification, Rolling Stock, and Customer Services.