Persephone and I are nomads who live in our 17' travel trailer. The trailer is too small for a tower and Persephone wants to be up high. She tries to get up on the top of the window valances but they are too narrow. I don't wish to drill holes in trailer walls but I want to put some kind of perch or walkway for her higher up. Is this even a possibility? Maybe something I can set on my bed that goes above the top of the window? Below is a photo of window in our sleeping area.