The idea of climate pilgrimages was developed in the framework of the Pilgrimage of Justice and Peace launched by the World Council of Churches at its 2013 assembly in South Korea.
The path led from Bonn, Germany to Katovice, Poland, where COP 24 took place in December. The pilgrims visited "places of strength": positive examples of sustainability, and "places of pain", e.g. active lignite coalmines and coal power plants. On the way devotions, discussions and workshops took place.
You can download the booklet here (in German)