What is the closest you can legally get to the approach zone on a runway, without of course being on an airplane or working for an airport?
My own experiences...
Back in the late 1980s the best area I knew of was DFW's Runway 18R approach end (on the northwest side of the airport). The spot was among the approach lights, 950 ft from the runway threshold, and looked DOWN on the runway slightly (all this data is for those of you who haven't been there). It was a tremendous thrill to watch the 767s and 747s come overhead, and you could actually hear the wake vortices following DC-10s about 20-30 sec after they passed overhead. Around 1994 the airport owners decided to close the road to public access and created a very tame viewing area on the southeast side that's a good 1/4th of a mile to the SIDE of Rwy 35C. :-( It sucks so much that I only visited it once, though it's probably good for casual photography with a telephoto lens.
Over the years I tried scouting out viewing areas at SAT, LAS, OKC, FAI, etc, and had no luck finding anything remotely similar to the old DFW 18R vantage point. In many cases I couldn't even find a spot near the approach end that wasn't hidden by some embankment or a huge fenced buffer zone.
In your opinion, what is the BEST airport for spotting at, and the WORST, in terms of viewing areas? My "worst" pick is San Antonio, hands down -- I circled the airport by car and was never able to even get a glimpse of the runway except from busy Hwy 281, and no place to park there.