The ridge walk is an absolute must while you're in Ubud. Walking out of Ubud to the west you will see the Ibah hotel on your right as you go down the hill to the river in Campuhan. If you go into the driveway of the hotel there is a small sign that points you in the direction of the Campuhan ridge, a gorgeous walk through rice fields overlooking the Wos River. To Karsa Kafe, which is just about the top of the route and is a great place to rest and have a drink, is probably about a mile and a half but you can do it at a very leisurely pace. The walk back down is easy. Don't miss out on this beautiful walk!