I know the park you're talking about, been there many times myself. As a kid, I used to spend hours with my dad watching planes at MSP. We had an air band radio so we could listen to the tower, and a notebook where we would write down tail numbers and what kind of planes they were. We would usually sit off of Post Rd, either at what they now call the "cell phone lot", or farther down where the big taxi lot is now. Of course, those were the days when 90% of the planes at MSP were Northwest instead of Delta, Runway 17/35 didn't exist, the 12/30 runways were 11/29, and you could go walk around inside the entire airport just for something to do.