I need help from you experienced travelers. We booked the Valley of the Kings ship excursion in Luxor, but I am worried about the level of difficulty. It says it is strenuous, but I am wondering what makes it strenuous? Is it the very long day, a lot of walking, a lot of steps and difficult walking surfaces, all of the above? I am mobile but I would like to enjoy the tour and not be exhausted and having to be overly vigilent about my footing throughout the tour and not be able to see what I came to see. Many thanks for your input! P.S. I asked the Excursion Desk and they had no idea except what was in the description of the tour.