Very simple and beautiful, go to Watamu, near Malindi in the north. It has the best easily-accessible marine park in the world, which you can swim out to from the beach or take a small boat. The reef is not far and you can swim beyond if your a good swimmer, the rest you just flow with the current.
There are great reasonably priced hotels and resorts and white coral sand beaches, no chavs from down south and you can get in a short safari as well. Should cost about £1,000 for ten days. Family friendly.
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