The Rumpus Bar is a fabulous bar to be found at the top of the Mondrian Hotel on the South Bank with the most enormous panoramic windows giving a fabulous view of London with St Pauls slightly to the right and various other landmarks visible from the top floor of this quirky & arty hotel. There is a terrace but sadly it was raining when we visited so everyone stayed inside where you could still enjoy the view of London and The Thames blow. The walkie talkie building is very close by on the same side of the river. You take the lift to the top floor from the trendy and arty reception. We were greeted by some very stylish staff who were very welcoming. The drinks are not cheap at £14.50 (but it was a 50ml gin) gin and tonic. Nice glasses and well presented. A few friends were drinking wine and also made comments about the drinks possibly being on the high side but I suppose it must be so popular on a great sunny day! It was very busy when we left to have dinner a couple of hours later. All in all a highly commendable bar in the heart of the city with a superb restaurant in the basement.