Ollantaytambo Ruins

There are many options for exploring the archeological park. Private or group tours include day trips from Cusco or multi-day tours combined with visits to Lima, Machu Picchu, and various towns in the Sacred Valley, such as Chinchero, Moray, Pisac, and Maras—each with their own worthy attractions. Other tour options make the most of the the exquisite scenery on mountain bikes and ATVs, and most include transportation, entrance fees, accommodations, and guides.

• Ollantaytambo Ruins is a must for archaeology and history buffs, as well as first-time visitors to the Sacred Valley.

• Wear comfortable shoes, as you'll be walking a lot on uneven stones. The best view—a panorama of the remains of several temples and ceremonial fountains—is atop 200 steps.

• Because of the high altitude, be sure to stay hydrated and take it slow. Chewing on coca leaves or drinking coca tea helps alleviate symptoms of altitude sickness.

• Tours operate in all weather conditions, so remember to dress appropriately: sweaters for colder months and a rain poncho for rainy season.

The Ollantaytambo Ruins are about 12 miles (19.2 kilometers) from Urubamba, and 37 miles (60 kilometers) from Cusco. Trains running between Cusco and Aguas Calientes (for Machu Picchu) stop at Ollantaytambo, which is the halfway mark along the route. Alternatively, many tours include round-trip transportation.

The archeological park is open daily from the early morning until the evening, year-round. Arrive early for a less crowded visit, before the tour groups arrive. Dry season in the Sacred Valley is from May to October, and rainy season generally spans January through April.

Follow the 3.5-mile (6-kilometer) trail to the quarry on the other side of the river to see where the Incas procured the immense stone blocks for their construction. Ever the ingenious builders, they diverted the river to flush the stones down to a construction site.