Attaching two pictures of Daytona International.
First, the retail-dining-entertainment-corporate HQ area on the north side of US-92 was all private commercial property that was acquired by ISC (now merged with NASCAR). I have outlined the area in purple highlighter to give a sense of how large that area is. It's bigger than the mall next door. It's about half as large as the speedway itself, which is a 2.5 mile tri-oval track.
Second, there are two pedestrian bridges outlined in green highlighter. Since the superstretch (backstretch) grandstands were knocked down, the frontstretch grandstands can hold 102,000 people, and that is not including the people allowed in the infield (camping). The total number of people in all areas will be between 120,000 and 125,000 this weekend. US-92 is an 8-lane divided road (comparable width to the Palmetto). So, yes, it is very possible to move 100,000 people over pedestrian bridges. And before all of the reconstruction, the Daytona 500 could hold 150,000 to 175,000 people and there was only 1 pedestrian bridge.
Third, there are two tunnels that go under the speedway for infield access, and these are open all race long. You can see the Turn 4 tunnel to the right of the Richard Petty Driving Experience in the first screenshot, and the huge Turn 1 tunnel (18-wheelers can drive through it in both directions at the same time) is just outside of the lower left corner of the screenshot, down by the Cracker Barrel. It would not be difficult at all to build tunnels under the Palmetto that would allow traffic flow for shuttles, buses, etc. on game days, or even to elevate the Palmetto for a half-mile stretch.
Finally, I'll post a second screenshot which shows the remote (and free) parking lots. Shuttles are run constantly before and after the races. I'm not saying this is cheap, but if you think about it, an entire fleet of shuttles is maintained by ISC/NASCAR for what is, essentially, two race weekends per year.
The reason I suggested the commercial/industrial area to the east of 826 is because it could serve as parking for both Tropical AND Doug Barnes park on the north side of Bird. Again, I would love to see MORE park land, and I think that the creation of a common parking area for both parks would allow the existing land to be used more heavily for the park amenities. Don't even get me started on how Disney moves people around, I was just out there for a tax conference.
Retail/dining/entertainment/corporate HQ area in purple (formerly private commercial property purchased by ISC), pedestrian bridges in green:
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Free, remote parking (shuttles running all-day on racedays):
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