How much training is needed for the Camino?

This question came up the other day. 

photo of woman carrying black bag
Photo by Spencer Gurley on

We are 3 girls doing a 5 day walk only. Our first time. It might be this distance.
My question is, how much should we practice/walk before we get there?
I found recommendations saying that I for a periode should walk 20 km 3 times a week – but I assume that is if I’m doing a longer distance. Not only for 5 days… Or what do you think?

How much did you train/walk before you went?