It might be interesting to trace which famous people have visited the Grand Canyon. Certainly Theodore Roosevelt, who was instrumental in the creation of a National Park System, made historical speeches there. And, of course, various stunts have been performed there; for instance, Evel Knieval, the cult leader of stunt motorcyclists, attempted to jump Snake River Canyon in 1974.
A couple of other possible things to talk about, depending on what interests you and what your paper is supposed to be about:
- How did the Grand Canyon come to be a national park?
- What rights should Native Americans have in terms of controlling access to the canyon?
- What environmental issues face the Grand Canyon?
All of these are potentially interesting topics. You need to determine which of these things your essay will address before you can write a thesis statement.