We decide to take the 11-kilometer-long Alkali Flat Trail. Before starting off on the trail, we have to sign a book to tell the park rangers how many people are in our group and the time we start our hike. When we finish hiking, we will sign the book again to let them know we have returned. The park brochure says this trail will take us to the edge of the monument where the white sands end and the normal desert begins again.