A few months ago, you could find the "Stempelstelle" from the "Harzer Wandernadel" No. 1 here, and you could find it by searching "HWN 001". There are 222 "Stempelstellen" (please see https://www.harzer-wandernadel.de/stempelstellen/gps-download/), and all of them could be find with the pattern "hwn <nnn>" and I used this a lot - if this could reinstantiated, I would very much appreciate it.