Michael Portillo has reached Lincolnshire, where his coastal railway journey from Middlesbrough ends. In Grimsby, he investigates an important new stage in the town's history - as a maintenance base for some of the largest wind farms in the world.

In neighbouring Cleethorpes, Michael is excited to ride on the Cleethorpes Coast Light Railway, pulled by a miniature steam locomotive, and on the shores of the mighty Humber estuary, Michael meets the Humber King, who holds the record for swimming across the Humber.

From Cleethorpes, Michael makes for a curious and wild stretch of coastline at Humberston. At Young's, he learns how half of all scampi produced in the UK is made – and tries it himself.

Michael Portillo is in the glens of Antrim, where Ireland's folklore and magical myths flourish and he is transfixed by tales of fairies and legends of the sea.

At the entrance to Belfast Lough, in Whitehead, he discovers a glorious museum, which tells the story of Ireland's railway heritage. Meanwhile, on the seafront, Michael joins a crew belonging to the Whitehead Coastal Rowing Club as they prepare to race.

At the medieval Carrickfergus Castle, Michael learns of the town's important role in the history of Ireland, when William of Orange landed at its harbour and went on to fight the Battle of the Boyne.