If ever you find the Central Market such a huge place, then you should go visit the Night Market instead. Not all the goods there would be here though but you surely can get all the little souvenirs that you need to bring home.
My personal favourites are the creatively quaint nail-clippers. At a glance they may look like key holders but they're not. I also bought a cheap crystal encrusted watch bracelet for just USD5. You can find jeans, larger t-shirts, fabric handbags and all sorts of other crafts here.
At the end of the market, there was an eating section for the locals where they all sat on combined mats and mingled with each other. You can join them if you want.
All in all, it was a pleasant walk in the evening to remember and you can support the Cambodian home industries by buying some things there as well.
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