Caral is according to the current science the oldest town in the Americas. For its age of up to 5000 years a lot of the ancient city is remaining. You can see pyramids. Most of them have been freed of the sand and stones that covered them. One still looks similar to its status when it was discovered. Apparently it was discovered by its form from a bird eye perspective because from the ground it looked like natural hills. The other pyramids have been freed from the errosion. They remained untouched for about 3,800 years.  
 
There are buses from Lima to Barranca and/ or Supe. We can recommand the cheap Hostal Los Angeles for the very informative and kind woman that runs it.  
We stayed in Barranca and went to the transport company ET Valle Sagrado Caral that took the two of us exclusively for 40 /S to the entrance (Boletería). We took the obligatory tour in Spanish with a good guide. The entrance fee is 11 /S p.p. and the tour costs another 20 for a maximum group size of 10 people. As we had a big group we paid only 5 /S for the tour. It lasts 1 hour and gives you closer views of the different pyramid ruins plus verbal explainations in Spanish. The English text signs along the paths are in my view completely unuseful because the only moment when you can read them is during the Spanish explainations. It is prohibited to walk through thw site without a guide. After the tour we had a hard time reading through all the info plaques in Spanish in the entrance area which seemed to be interesting. Finally we found out that in the small museum building area again the same info signs but there they are bilingual including English. To get back we waited 50 minutes until our transport filled up with people that had already pre- arranged the ride back to Barranca. We could negotiate a price of 10 /S per person. By the way if you can't get enough of Caral: In Supe there is also a museum at the plaza and close to Supe is the Site El Aspero which was the fishing site of the civilization. 
 
All in all it's cool to have visited the oldest city in the Americas. When we were there it's in the end sandy and stony pyramids in a desert above a fertile river valley running into the Pacific. There are less details and art to be seen here than in other arqueological places like Tiwuanako but then again it's also much older. It's nice for a one time visit.