They were a familiar sight on the railways at the dawn of diesel.

But after a 30-year absence, a fleet of four Class 37 engines was pressed back into service on Norfolk lines, to meet a shortage of more modern locomotives.

And the return of the 1960s trains caused such a stir among rail enthusiasts that a special outing on them is taking place today.

It will raise vital cash for East Anglia's Children's Hospices (EACH).

The special service, formed of four MkII carriages top-and-tailed by two Class 37 diesel locomotives, will run fans from Norwich to Ely and from Norwich to London, on a charity charter,

The Class 37s have been in regular use for almost two years on the Norwich to Great Yarmouth and Lowestoft lines.

Although they have been in operation for 50 years, it is more than 30 years since they were regularly in use on passenger services on the Norwich to Ely and Norwich to London routes.

Jonathan Denby, of Abellio Greater Anglia said: 'We're delighted to be running this special EACH Express Class 37 railtour to raise funds for East Anglia's Children's Hospices.

'It's an extremely worthwhile cause focused on the region we serve and supported by many of our employees.

'With a fully booked train and 200 tickets sold, more money raised by auctioning cab rides between Norwich and Ely and further funds raised on the day, we will be able to generate an impressive contribution to EACH funds.

'Taking in two routes which have been synonymous with Class 37 locomotives in the past, it also promises to be a great day out for all involved.'

Lotte Rietveld, of EACH, said: 'We'd like to wish everyone on this special one-off charter train journey a lovely trip.

'We're so grateful to Abellio Greater Anglia for their generosity.'

A raffle will be held on the train today, with the service departing Norwich for Ely at 10.15am, and for London Liverpool Street at 1.33pm.

Funds raised will help the EACH nook appeal.