These were operated by Cambridge Class 101s.
The extension of the Moorgate - Hertford North service to Letchworth from 14 May 1979, worked by Class 313 EMUs, saw this DMU service reduced to Hitchin - Huntingdon, but increased to an hourly frequency.[1]
This measured 4 1/8" x 3" when folded.
A refurbished Class 101 is seen at Hertford North after arrival from Huntingdon in the late 1970s. John Law.
A refurbished Class 101 dmu (51443 closest) on the last day of the Huntingdon service at Hertford North in 1979. John Law.
Audley End-Bartlow
Boston-Lincoln
Cambridge-Ely
Cambridge-Ipswich
Cambridge-Mildenhall
Cambridge-St Ives
Camden Road-North Woolwich
Cleethorpes-Barton-on-Humber
Cleethorpes-New Holland Pier
Colne and Stour Valley Lines
Doncaster-Cleethorpes
Ely-March-Peterborough
Grantham-Boston
Grantham-Lincoln
Grantham-Nottingham
Grantham-Skegness
Harwich-Manningtree
Hertford North-Huntingdon
Ipswich-Felixstowe
Ipswich-Lowestoft
Kings Lynn-Hunstanton
Lea Valley Lines
Lincoln-Cleethorpes
Lincoln-Sheffield
London-Hertford North
London-Welwyn Garden City
Lowestoft-Yarmouth
North Walsham - Mundesley-on-Sea
Norwich/Cromer- Melton Constable
Norwich-Ely
Norwich-Kings Lynn via Dereham
Norwich-Lowestoft
Norwich-Sheringham
Norwich-Wells via Dereham
Norwich-Yarmouth
Peterborough-Grimsby Town
Peterborough-Cambridge
Romford-Upminster
Royston-Cambridge
Saxmundham-Aldeburgh
Sheffield-Barnsley
Sheffield-Cleethorpes
Sheffield-Doncaster-Hull
Sheffield-New Mills
St. Margaret's-Buntingford
Sudbury-Colchester
Thetford-Swaffham
Wickford-Southminster
Willoughby-Mablethrope
Witham-Braintree
Witham-Maldon
More lines will be added in the future!