It's the locals showing up as school gets out. Wednesday is the last day for Broward schools. And yes, 11am is the time everyone shows up. They all sleep in, and arrive to the park at the same time. If you can wake up early, you'll have 2 hours of the park to yourself. Even with FOTL it's good to arrive early as the walkways get crowded. Go to lunch at 11am to beat the crowd.