Is this where we met with you guys?
Actually, the meetup is supposed to be at Old Settler's Park in Round Rock. However, it has started to get way too crowded as of late, so we've been meeting at various other places to see what options there are. Mostly, it's been at other, smaller parks around Lake Georgetown because they are easy to get to and have facilities. However, they are still just parking lots which can have other people show up and make space an issue if a lot of us show up. The bridge mentioned is clearly not going to have the same level of visitors since you're sitting, well, under a bridge. It's also cool that it's not in anyway a maintained road. So, for a monthly meet, it's slightly off-roady.
You can go to Google Maps here (30.610149421050387, -97.81840583880815) and take a look.