We are building a park locator webapp that allows you to select multiple amenities (similar to the one seen here or in the image below). The problem is that there is such a long list of filters (we have more than are on that particular webapp), that it makes it difficult to figure out what options are available if you don't know exactly what you are searching for. We would like to have the ability to "group" or "nest" the filters together so that you could have all of the general, athletic, or passive recreation amenities grouped together. You could open all of the categories if you want to see all of the filters at once, or you could close out all of the athletic filters so you just see all of the passive recreation listed.
