Columbia ended a 30+ year war with FARC, a brutal guerrilla army, by using negotiation rather than weapons.
Considering all the awful stuff FARC has done (executions, drugs, kidnappings, child soldiers) and vice versa in some cases (killing civilians and calling them rebels in order to look effective in the eyes of the people), it's really impressive that they were both willing to forgive each other in the name of peace.