We got a combined ticket to see the museum and the snake park (I had visions of a snake park being filled with slides and swings specially built for snakes but, sigh, can't have everything...). As a combined ticket, it's worth it as it only costs 300 Ksh more to see both. If you just bought a ticket for the snake park (or indeed just for the museum) I think you'll be disappointed.
Definitely go round with a guide. Ours made the trip soooo much better as he knew lots more interesting stuff than just the information on the labels. It is old and in need of a big re-vamp and the aquarium bit is fairly pointless - and I felt sorry for the alligator (the only one in Kenya) who has been there for every one of his 46 years with no one to play with.
Learned a lot about snakes and filled an hour very well, but wouldn't have been good value on its own.
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