Episode 4/5. In 1705, the 20-year-old Johann Sebastian Bach set off from his home in Arnstadt to walk 250 miles to Lübeck, there to meet his hero, the composer and organist Dietrich Buxtehude. In the fourth of five "slow-radio" walks in which writer Horatio Clare searches for Bach's footsteps - and his ghost - Horatio Clare searches for his footsteps - and his ghost - the route takes him along the banks of the River Ilmenau from Medingen to Bienebuttel.