I live in Bournemouth and am happy to give you some hints and tips. The Bournemouth Marriott has a lift down to the beach, of which there is 7 miles of sandy beach to choose from. You can get to several places of interest from here. I would recommend a restaurant approx 2 mins walk away (the Ocean Palace) This is a fab chinese restaurant, on Sundays they do a great buffet for about £10 pp at lunch times.
The Bournemouth exhibition centre(is a short walk away and they will have entertainment there, or across the road(go via the beach, no traffic!) at the Pavilion. If you have any particular interests, let me kniow and Ill have as look around for you and send more info.
I have also stayed at the County Hall Marriott, beautiful hotel and views from most rooms. It is a good taxi ride to theatre land, if you are happy going underground I recommend crossing the bridge and using the station opposite big ben/house of parliament.
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