This is a lovely apartment located so close to the Guggenheim that you can take a rest mid day in your museum excursion or return later in the day to see evening lights.
We also loved that it was half a block from airport bus stop which made getting to/from airport a breeze. Iker left us a great list of places to eat and other things to do while in Bilbao. He is a wonderful host and his place is a perfect place to enjoy your stay in Bilbao.