Even though they're not really a chain, YMCA membership is another option. Each Y is locally controlled and not all allow other Y members to use their facilities, but most do. Most allow free use, but one I went to charged a $2.00 daily fee for other Y members. Some also impose restrictions such as only allowing 15 visits a year by members of another Y. The biggest advantage is that there are a lot of locations. The biggest downside is that quality is very variable. Some facilities are new and well equipped, some are in sketchy areas and are old and run down.