TV Guide BBC Two Tuesday

Cameras follow Radio 2 DJ Sara Cox as she takes on her Great Northern Marathon Challenge, a five-day trek in which she jogs, runs and walks 135 miles through the wild beauty of Northumberland National Park, climbs up into the Pennines and journeys across Yorkshire while carrying a Pudsey Bear backpack. He aim is to reach Pudsey in Leeds, the town that gave the Children in Need mascot his name

Becky Houghton is presented with a cracked violin that once belonged to a Jewish musician who was imprisoned - along with his instrument - in Theresienstadt concentration camp during the Second World War. An Aberdeenshire woman and her mother arrive with a weather-beaten enamel sign from the family's long-gone Highland garage business, a North Yorkshire man brings in a ceramic birdcage that has seen better days and a former rock 'n' roll roadie asks the team to bring his old leather jacket back to life

The three remaining chefs from London and south east England cook mains and desserts, celebrating great Britons of the past. Lisa Goodwin Allen judges their dishes, which include an elevated chicken soup, celebrating Amy Winehouse, and a pistachio and white chocolate cheesecake with a black cherry gel centre

It is judging day, and only one chef can go through to represent London and south east England. Archdeacon and campaigner Mina Smallman helps decide the winner from the two remaining chefs. Andi Oliver hosts

Liz explores the volcanic islands of the Lesser Antilles, joining residents of Mayreau who are repairing their island's vibrant coral that has been damaged by disease. On neighbouring Union Island, Liz goes on patrol with an environmental army protecting the Union Island gecko, one of the smallest reptiles in the world and which was once one of the most trafficked reptiles in the Caribbean

Paul Martin presents from the RAF Museum at Hendon in London, where items up for auction include a nautilus shell and some Superman film memorabilia. With antiques experts Michael Baggott and Mark Stacey

The teams race from the surf mecca El Zonte on the Pacific coast across the entirety of El Salvador, known as the land of volcanoes, before entering Honduras to reach the third checkpoint, the colonial mountain town of Valle de Angeles. With the gap between teams reduced to just three and a half hours, Anita Rani and Bal Nazran are first to depart, eager to maintain their lead. However, Roman and Harleymoon Kemp hatch a plan to steal first place, by speeding along the coast to enter Honduras by sea

Singer and actor Antony Costa, Paralympian and actor Gaz Choudhry, drag artist Ginger Johnson, actress Katie McGlynn and reality star Uma Jammeh compete in the first heat of the celebrity contest. Judges Grace Dent and John Torode challenge them to make a dish using a secret ingredient, before a blindfold test in which they must identify cubes of meat, fish or fruit by touch and taste only. Finally, they have one hour to cook a dish for their own food stall

Mary Berry is joined by broadcaster Alex Jones and they celebrate how Mary's friends and family, as well as the viewers, have been at the heart of her cooking for 60 years. Together, they cook a cheesy mushroom and spinach lasagne, a reinvention of Mary's 1970's chocolate cake, her husband Paul's favourite cheesy nutter snacks, and her Victoria sandwich

David explores the contested histories and modern hybrid identities that were left behind when, after four centuries, the British Empire finally came to an end, just decades after reaching its maximum size in the wake of the First World War. He also reveals how members of his own family were connected to the Empire as both colonisers and colonised, showing that this controversial and complex story is in many ways a messy and shared history