Countryfile is in Snowdonia where, with the help of some recently unearthed BBC archive, Adam Henson is discovering how farming has changed in the past 60 years. He also looks back through Countryfile's own archive to the times the programme has explored farming then and now. From when Matt Baker put a Little Grey Fergie tractor to the test to when Adam discovered a space-age underground farm in the heart of London.