Alan concludes his journey and questions what the future might hold for the landscape and its wildlife.
Alan reveals a hundred years of change to our countryside, including some unexpected alterations to Northumberland using high explosives.
Alan explores a time when industry changed the landscape, and the rocks and minerals beneath our feet helped build an empire.
Alan Titchmarsh discovers how our ancestors - from Stone Age man to the Romans and Normans - not only changed the countryside but also brought us the scourge of gardeners everywhere.
When the Ice Age ended and the seas rose twice the height of London's Telecom Tower; people be came cut off from mainland Europe; a dark and dense wildwood covered most of the islands.
Alan Titchmarsh looks back to the last Ice Age and reveals how a mile-thick layer of ice covered Birmingham and that Scotland had polar bears; he also finds out what its like to be a Neanderthal.