I have a 5' iron fence in my backyard, which sits on a 1-2' wall. How high does a wire fence need to be sitting on the wall, which again has a 1-2' height? The rabbits now come between the iron fence.
Keeping Rabbits Out
Certified GKH Gardening Expert
Probably 24" would be enough. I imagine that the rabbits are hopping onto the wall and then back off the wall into you garden. The wire fence will keep them from being able to make the hop down. Without a running start, they will not be able to get much height to get over the wire. This article should also help you with your rabbit problem: https://www.gardeningknowhow.com/plant-problems/pests/how-to-keep-rabbits-out-of-gardens.htm