I visted the Temples of the Sun and the Moon on the same day. The Temple of the Moon was interesting, fascinating and well presented.
In my opinion, you might consider passing on Chan Chan. Take a look at a photo on Google Images (pretty much any photo.) That about sums it up. One of the less interesting ruins or archaeological sites I've visited.
On the other hand, these sites are near each other and entry was only 10 Soles ($4.00,) so give it a go if you're so inclined.
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