These tours are tailored to your specific needs. Some people will want to walk back and forth as much as possible others will want to take it easy. Some photographers like to get into one spot and stay there. So it is up to you really. The whole walk from one end of the Falls to the other is about 1.7kms so if you did the full length then it is about 3.4kms. At some times of year this is possible and necessary to get good rainbows but at other times like now in April in flood season there is no point in walking to the end to get rainbow shots as there is too much water and spray.
The paths are very good and the walking is very easy.