From what I've herd, chinle will be awesome if you can get it, for the hiking options. In general, I wouldn't worry to much about not even camping at all between mile 13 and 20, the river moves really well through that section, you could even do a double layover day with that 4 days, if you wanted. G.F. and I stayed at the small camp at prospector loop last spring, and spent a quality afternoon floating laps in the river in front of camp. ( River right mile 11.2)
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