Beylerbeyi Palace sits on the Asian shore of the Bosphorus, just south of the first Bosphorus Bridge, and can be reached by ferry from Beşiktaş or Kabataş in about 20 minutes. Built in 1865 as a summer palace and guest house for visiting foreign dignitaries, it received Napoleon III's wife Empress Eugénie on her way to open the Suez Canal.
The interiors are extravagant — Turkish crystal chandeliers, Chinese porcelain, marble bathrooms — on a slightly smaller and more intimate scale than Dolmabahçe. The palace garden terraces dropping to the Bosphorus are a good reason to visit even if you skip the interior tour. Often overlooked in favour of Dolmabahçe, it's worth the ferry journey for those with time.