This is a commemorative pin for the "21. Dreikönigswanderung Rieschweiler 1988."
The pin depicts a nativity scene with the Holy Family in a manger.
"Dreikönigswanderung" translates to "Three Kings' Hike" or "Epiphany Hike."
Rieschweiler is a village in Germany.
The pin commemorates the 21st annual event in 1988.