The oldest city in the Americas
Caral is a UNESCO World Heritage site about 5000 years old, discovered in 1948. This is considered the oldest city in the Americas, built 3000-2600 BCE. Archeologists have found artifacts such as quipu (knotted ropes used to record information) which show how advanced the society was at a time when complex societies were also forming in Mesopotamia, Egypt and China.
The site is well preserved in part because it was abandoned early and discovered relatively recently. In 1997 Peruvian archeologist Ruth Shady announced the discovery to the world. There was also a set of 32 flutes found, made of condor and pelican bones.
If you are interested in archeology, Caral should be at the top of your list for places to see in Peru, tied with Machu Picchu.
Related to Caral, and relatively nearby, are Àspero and Vichama. Áspero is open every day 10am-6pm. Vichama is open Mon-Thurs 9am-4pm and Fri-Sun 9am-6pm.
Caral is about 3 hours north of Lima, about 20k inland.
The archeological site is open Mon-Thurs 9am-4pm and Fri-Sat 9am-6pm.
See Caral visiting infomation here.