There are some groups that organize tailgating. See the links below. The quality of the team the last couple of decades has had an impact on tailgate enthusiasm somewhat but there are still many groups of people tailgating in the lots before games. Some of them like tailgaters make it a part of the experience.

http://www.boldcitybrigade.com/gameday/
https://twitter.com/tealsthooligans

Coming to Jacksonville you should get out to the beach for a day or two. Depending on what you're looking for, Avondale and San Marco have some eclectic pubs and places to eat/drink/hangout. St. Augustine is cool for a more traditional tourist experience if you're into that. If you like to golf, there are some great courses in the area, including Sawgrass which is where the TPC is played.

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