We took a private driver from Cusco to Pisac and spent a half day hiking around the ruins. The valley makes for great pictures - this site can be windy so dress warmly. You should purchase the Cusco City Pass if you plan to visit a lot of SV sites. We opted to do a half day tour of the ruins/market and then went back to Cusco for more sightseeing in the evening. It's possible to take the bus if you wish - but we didn't explore that option. We went on a day when the full market was not operating, but there still were some vendors around. The market seemed pretty touristy and there was not much else to do/see around the town. There is a full day tour that covers Pisac/Olla/Chinchero in one day but we felt it would not do justice to the Sacred Valley and it also leaves out Maras/Moray which were phenomenal sites.
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