Link, and a fleet of , and units from Wessex Trains. Inter-City services Class 800 Intercity Express Train Most Great Western Railway intercity services are operated by a fleet of 57 Class 800 trains from the Hitachi A-train family. GWR operates most of its long-distance services between London and destinations such as , , , , , , , , , , and , using these trains, which gradually replaced the older InterCity 125 sets between autumn 2017 and spring 2019. On 28 April 2021, six Class 800s were withdrawn from service due to cracks being found during maintenance and were sent to Hitachi for inspection. Class 802 Intercity Express Train GWR operates most long-distance services between London and destinations in the west of the network (such as , , Plymouth and ) using its fleet of 36 Class 802 trains, the first of which was introduced on 20 August 2018. These trains are almost identical to the Class 800 trains, except they have a higher engine operating power— per engine as opposed to —and are fitted with larger fuel tanks to cope with the gradients and extended running in diesel mode on the long unelectrified stretches in Devon and Cornwall. Hitachi planned to test a tri-mode Class 802 in 2022 fitted with batteries in an attempt to reduce emissions entering and leaving stations. Sleeper services Class 57/6 + Mark 3 Four Class 57/6 locomotives haul Night Riviera Sleeper services, and failed HST sets. When these are unavailable, GWR hires Direct Rail Services Class 57/3 locomotives to operate the Night Riviera. Thames Valley and Bristol services Class 165/1 Networker Turbo The "Networker Turbo" is a two- or three-coach DMU used on shorter-distance services in the Thames Valley area, with the majority based at Reading Traction Maintenance Depot. They are mainly used on branches such as the Greenford branch line, Slough–Windsor & Eton line, Marlow branch line and Regatta Line. They are also used on services between Reading and Basingstoke, Didcot Parkway and Oxford or Banbury and sometimes services between London and Oxford. Some (eventually all) are based at St Philip's Marsh depot in Bristol, where they work on the most of the lines in the area including the Severn Beach line, Heart of Wessex Line, Golden Valley line and Bristol to Exeter line. From summer 2018, they are due to run on Cardiff Central to Portsmouth Harbour services too. In