BILLY Connolly has previously biked along Route 66, but for his latest trip across America the comedian is letting the train take the strain.

The 72-year-old star is to travel across mainland United States by rail in new ITV documentary series Billy Connolly’s Tracks Across America.

Connolly – who in 2013 confirmed he was being treated for the initial symptoms of Parkinson’s disease – will cover 28 states and 8000 miles on his train journey through mountains, desert and swamp, starting and finishing on the East coast in New York.

In the heartland of America, from North Dakota to Louisiana, the funnyman will seek out interesting characters who capture the spirit of the country, as well as regaling viewers with tales of the outlaws and stars who have travelled along the same tracks.

The series is directed by Mike Reilly who worked with Connolly on the 2011 series Billy Connolly’s Route 66 which saw the Big Yin turn Easy Rider.

He said: “I can’t think of anyone better qualified to undertake this journey than Billy, his love of America, its people and music combined with his one of a kind wit and skewered powers of observation will make this show a joy to be part of.”