Anyway, the US lower 48 airspace is divided into 20 zones. There is an ARTCC in Alaska, which I've included in this survey, but I couldn't find any imagery on the one in Hawaii, so I didn't include it. I suspect that ARTCC is located at Honolulu International Airport or somewhere close to the airport. There are probably 22 zones in the entire US system, but I'm not too clear on that aspect.
Do not confuse a control tower at the airport for an ARTCC. They are not the same thing. Although many ARTCCs were co-located at major airfields, they are actually seperate facilities. Some were not even at an airport, but were located a few miles from an airfield. However, they all shared these characteristics:
1. They all had ample parking for the employees.
2. Nearly all were protected by one fence layer and contained a guarded entrance.
3. All ARTCCs that I observed contained what looked like a microwave tower or communications tower. To get an idea of what they look like from the ground, take a look at the ZAU-Logo.jpg image for ZAU. All ARTCCs had at least one of these, however, some had two and even three of them.
Other site identifiers for an ARTCC that stood out were that some, but not all, had satellite dishes oriented to the south, which I believe where communications dishes pointed towards geosynchronous-orbited satellites. Some ARTCCs had a triangular-like yagi antenna, too. A good example is the zau_artcc2.jpg shot for ZAU. Look for it on the southeast corner of the facility.
As for what airports I decided to include with the ARTCC report, I started at the FAA web site. The zone maps which show the ARTCC's included airfields came from their web site at http://www.fly.faa.gov/ois/. However, I came across other information which stated other airfields might contain TRACONs at their facilities, so this became somewhat confusing. As a result, I may have included airfields which play no real part in ATC functions, and may have omitted others. Frankly, some employee of the FAA should be doing this project instead of me, but then, I doubt they would've added the Air Force One variable into the equation. So, I give you my attempt at trying to discern how Air Force One is related to the air traffic control system of the United States:
ZAB
ZAN
ZAU
ZBW
ZDC
ZDV
ZFW
ZHU
ZID
ZJX
ZKC
ZLA
ZLC
ZMA
ZME
ZMP
ZNY
ZOA
ZOB
ZSE
ZTL
An interesting link:
http://www.flyingsfo.com/Getting_what_you_want_from_ATC.pdf