Hen Party Ideas without the tack!

I'm planning a Hen Party for my best friend in October. I don't live in London so any insider info would be massively appreciated! She's 28 and wants no L plates etc, cocktails, dinner and dancing. Would like to make it a bit more exciting...any ideas?! Was thinking perhaps burlesque show or similar. There'll be about 15 of us and we'll be staying Old Street way so pref nothing massively far away from there.

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