Great place! Extremely central and right in the heart of the "casco antiguo". Anzu has put great effort into the place and it shows. It's well thought out and magnificent for a large or small group. We only stayed a day and a half in Bilbao and this apartment was perfect we were able to walk to all the great areas, we had great food options as well as shopping. Anzu also made great recommendations for some local places.
Note that parking is not easy to find but there is a parking place about five mins away, convenient and not super expensive ( max of $17 euros per day). Would def stay here again and recommend it to others.