Another usage controversy: Caminando is all right (and correct) but in cities I think paseando por las calles is more appropriate.
I use caminando where I would use 'hiking' or 'trekking' in English: If you are doing the Camino de Santiago, you are caminando (whether en bici o de pie). In April I hiked from Potes to the Santo Toribio Monastery in Cantabria (unos 2 o 3 kilometros: Caminando; como no?). All one must do is to get there to earn the Jubileo.