NINE classic heritage diesel locomotives are to feature in the Swanage Railway's Diesel Gala and Beer Festival.

The 17th year of the annual festival will feature an intensive three-train service with most trains operating along the entire nine-mile railway line.

Seven of the locomotives will be travelling to Purbeck heritage line for the event from the national railway network.

It will be the first time a Class 52 'Western' diesel-hydraulic locomotive has visited Swanage since 2011 and the first time a Class 52 'Western' No. D1015 'Western Champion' has visited the Isle of Purbeck heritage line since 2007.

It will also be the first time a Class 69 diesel locomotive rebuilt in the last ten years from a 1970s Class 56 diesel locomotive - has hauled trains on the Swanage Railway.

The Diesel Gala and Beer Festival also includes a nostalgic 1966 'push-pull' 4TC four-carriage set, courtesy of London Transport, which operated between London and Swanage from 1967 to 1969.

Also appearing at the event will be the Swanage Railway-based Class 33 No. 33 111 which hauled the last 4TC 'push-pull' carriage set to Corfe Castle and Swanage on a Poole Grammar School railway society enthusiasts' charter train in 1971.

Another of the heritage diesel locomotives featured, Swanage Railway-based Class 33 diesel-electric No. D6515 'Lt Jenny Lewis RN', hauled the last train through Broadstone to Wimborne after British Rail closed the line to freight trains in 1977.

Event organising team member Dan Bennett said: "Our annual diesel gala and beer festival is an important and popular event in the Swanage Railway calendar while there is an ever-growing national following for heritage diesel locomotives, particularly among younger rail enthusiasts.

"Over the past 17 years, our diesel gala and beer festival has grown in popularity to become one of the most highly regarded annual events of its type in the country.

"A lot of detailed organisation by a small team of enthusiastic Swanage Railway volunteers and staff goes into planning the diesel gala with planning beginning four or five months before the event."

Diesel Gala and Beer Festival takes place from Friday, May 10 to Sunday, May 12. More details can be found on the Swanage Railway website.