Decathlon is unknown to US customers as they only recently opened in California, but it's a huge…read moresportswear and sports gear store with locations in Europe and Asia. Much bigger than Sports Authority, kind of like REI but with a better price. The place is very spacious, people can test out their bicycles up and down the aisles!
They boost that they have products for over 80 sports, and they are all private labels. That said, they will have something for many sports, but not necessarily a lot of selection for each. There are some lose-leader items worth checking out, like bag pack for 3€, or some other items for ridiculously low price. Some seems to be cheap for a reason - the stitching and material is just not that great, but they do have some nicer, higher end products that are thoughtfully designed and while not cheap, a good price compared to competition.