We visited this museum first on arriving in Valletta. It's not a very large museum (parts of it were being renovated while we were there) but there was enough to cover early Maltese history thoroughly. It doesn't talk about much after the Romans and is currently quite small, but there is a lot of information very well laid out, with lots of interesting artefacts recovered from sites all over the island. I would reccommend getting the Malta Heritage Pass, which is 35 euros, is valid for two weeks and then gives you entry to a whole range of sites on both Malta and Gozo. Most museums and sites are 5-9 euros for adult tickets, so if you visit the 4/5 in Valletta covered by the scheme and a few outside it, you've got your money's worth. Whether you get the pass or not, this museum is definitely worth seeing!
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