Kew Palace was initially bought by George III as a palace for the royal children. Many princes and princesses have been raised here! Later it was put into use as a summer residence for the British Royals.
The huge botanical gardens that lie around it occupy a whopping 121 hectares and have been on UNESCO's World Heritage List since 2003. The abundant flora and fauna will make you forget that you're in the London metropolis!
Otherwise very easy to figure out to book the tickets