This is an interesting place. It's right in the middle of fancy houses and mansions. It's smack in the middle of nice neighbourhoods, where the upper middle class lives. There's a small museum one can check out, which contains a few artefacts as well as mummies. And after the museum, one can climb up the archaeological structure, which is smack in the middle of the city.
The Huaca Huallamarca actually provides an interesting perspective on the city. When you climb up, you're given a great view of the financial district of Lima, which all the makes it funny that such an archaeological site is in the middle of it all.