When I did Caring for Giants, they made me leave my ECV next to a building and walk over to the truck. I remember them telling me "Oh, you won't have to walk far." Well, for me it was a very long, painful walk. I couldn't bring my ECV to the animal viewing area, but at least there, I could handle the walk. But for anyone unable to walk, it would be virtually impossible. However, I didn't call in advance to book it-I just booked it that morning at the location. However, the CMs could clearly see that I was in an ECV.