Highest climb achievement
This achievement is awarded to the geohasher who has traveled the largest difference in elevation between their starting point and the hash point entirely under human power (i.e. you have to CLIMB it). The travel can be walking, running, cycling, rock climbing, skiing (uphill!), snowshoeing, etc., but it must be unassisted by any non-human means--no hidden motors on your bike.
The most likely proof would be a GPS track and/or a picture of the GPS at your lowest and highest elevation positions between the start and the hash point.
Needs a ribbon!