in the last episode of this heart-warming series, the presenter tries to build the world's longest-ever model railway track, covering a 10-mile route between the Devon towns of Barnstaple and Bideford - which last had a regular train service more than 40 years ago. He is helped by thousands of members of the public, as well as wine expert and railway enthusiast Oz Clarke, but finds himself beset by the same problems that affect full-size train services - only on a much larger scale. Oversized leaves on the line and boulder-sized mounds of mud abound. There's more James May at 9.00pm with Top Gear (The hosts bid to prove that cars can be art by filling a gallery in Middlesbrough with motoring-related works, including a few creations of their own), but peppered in between are classics such as Dad's Army (8.00pm) and Blackadder the Third (8.30pm).