In 1916, the people of Mainz were invited to hammer a nail into an oak pillar. The mayor’s fundraising campaign sold nails at prices from one to 20 Reichsmarks, so people from all walks of life could contribute. It raised 170,000 Reichsmarks for war children’s welfare, holiday camps and soldiers’ families.

Other cities ran nail-pillar campaigns too, but this is reportedly the only pillar to survive. It was restored and returned to its place in front of the cathedral in 2011. A copy of the Iron Cross sits on top, with the inscription “God help us in times of war” and a verse of the patriotic poem Die Wacht am Rhein.

Both of VoiceMap’s Mainz tours stop at the pillar. They explain how the campaign worked, read out the inscription and say why this pillar is a rare survivor.