The rooms on London's South Bank can hold up to 150 delegates and unlike Merlin's other venues will be available for both daytime and evening hire.
As well as functioning as a standalone venue, it is hoped the Riverside Rooms will maximise packages at the neighbouring London Dungeon by offering an alternative dining option.
They will be officially launched with an exclusive party on 30 April showcasing all four spaces including the new London Dungeon inspired dining room.
Gareth McTiffin, marketing and events manager of Merlin Events London, said: "In the last six months we have seen an increase in bookings for private events, and the addition of the Riverside Rooms at County Hall will allow us to meet and surpass this increasing demand. Not only have we added another fantastic London location, we now have a multi-purpose space which will become our first venue available for day time events."
Merlin Events also manages functions at Madame Tussauds, Stardome 4D and SEA LIFE London Aquarium. Organisers booking the Riverside Rooms will be able to choose from add-ons including an after-hour’s tour of the Dungeon or VIP experience on the Coca-Cola London Eye.
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