A VINTAGE steam engine thrilled hundreds of rail enthusiasts on its return to mainline duty.

The Sir Nigel Gresley, an LMS A4 Pacific class 60007 engine, travelled from York to London Kings Cross yesterday.

Following refurbishment, the Gresley has been plying its trade on the North York Moors Railway for the past three years, operating from Pickering, via Goathland and Grosmont, to Whitby.

The engine earned its mainline safety certificate in April, passing a series of tests to assess its suitability for mainline duty.

Built in the Thirties the A4 Pacifics were regularly seen on the East Coast Main Line, operating from London to Scotland, setting a steam speed record of 125 mph.

The Gresley is one of only four A4 Pacifics left in existence.

Bittern and Union of South Africa remain on special mainline duties and the most famous of the class, The Mallard, lies dormant in preservation at the National Railway Museum, in York.

The Gresley set off from Grosmont on Saturday morning, making its journey via Middlesbrough, Northallerton and Thirsk before joining the service from York to Kings Cross.