Climbing irons were leg attachments used to make climbing wooden surfaces easier.
Climbing irons were metal rods that attached to the lower leg. A barbed ankle spike could be forced into a tree or wooden structure while climbing to ensure a steady platform for the feet. Many rogues used these to scale wooden building in cities.
The drawback of using climbing irons is that the wearers movement speed while on flat land was reduced by roughly 1/4.
- Aurora's Whole Realms Catalogue, p. 17.