The majority of replies is right -- get the RX10 Mark iii. If you want something smaller try the more pocketable Panasonic ZS100, but it only zooms to a 250mm equivalent. Both of these have 1" sensors, the smallest sensor that can get you good results. Most importantly, don't skimp! Spending more for a camera is much cheaper than having to fly back to retake your pictures. You will probably need a relatively fast lens and/or excellent stabilization because your tour will have you shooting while you bounce around on dirt roads. If you don't want to invest that much buy a very good camera anyway and list it on ebay when you get back.