These granaries/storage facilities were built at the same time as the fortress at Ollantaytambo. You see them and the path up to them from the fortress. The path starts from a narrow street in the town just off the main square. The path is quite steep - good practice for hiking/climbing the Inca trail and at Machu Picchu. You can climb, crawl over, around, through these ruins and wonder about life here at time of the Inca. Sit, relax and enjoy the views of the fortress, town and valley. Morning is a good time for the hike as the route is in the shade until about 11.00 a.m. Round trip depends on how long you want to spend exploring the ruins, but take your time (altitude), take lots of pictures and take a lunch from the town to make a day long picnic of it (definitely allow yourself at least 2 hours round trip from the the town square). Bring lots of water. The gate at the start of the trail is locked from dusk til dawn, so time your departure and return accordingly. Another reason to plan your trip and allow yourself time (a day is good) in Ollantaytambo, rather than rushing to Machu Picchu and back out again.
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