Here's the list of approved Shuttle landing sites... I'm sure if it was dropping out of the sky over Colorado they would try for Denver, but otherwise I don't think it's of interest to NASA ;> This is from the "Flight Maps and Charts" manual flown onboard, revised in 2003.
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SPACE SHUTTLE PROGRAM APPROVED LANDING SITES......................... 3-v
Tamanrasset, Algeria..................................................................................... AAT-1
Atlantic City International, Atlantic City, New Jersey ..................................... ACY-1
Hoedspruit AFS, South Africa........................................................................ AHS-1
Amberley, Australia........................................................................................ AMB-1
Amilcar Cabral International, Republic of Cape Verde .................................. AML-1
Bermuda International, St. David’s Island, Bermuda ..................................... BDA-1
Beja, Portugal ................................................................................................ BEJ-1
Ben Guerir, Morocco...................................................................................... BEN-1
Banjul International, Gambia ......................................................................... BYD-1
Dover AFB, Delaware.................................................................................... DOV-1
Dyess AFB, Texas......................................................................................... DYS-1
Elmendorf AFB, Anchorage, Alaska .............................................................. EDF-1
Edwards AFB, California................................................................................ EDW-1
Mataveri International, Easter Island (Chile).................................................. EIP-1
Esenboga, Turkey ......................................................................................... ESN-1
Fairford RAF, England................................................................................... FFA-1
Otis ANGB, Massachusetts ........................................................................... FMH-1
Le Tube, Istres, France.................................................................................. FMI-1
Francis S. Gabreski, Westhampton Beach, New York .................................. FOK-1
Las Palmas, Grand Canary Isle (Spain) ........................................................ GDV-1
Souda, Crete (Greece) .................................................................................. GSA-1
Andersen AFB, Guam.................................................................................... GUA-1
HAO Atoll, Tuamotu, French Polynesia......................................................... HAO-1
Ascension Aux AF, Ascension Island ............................................................ HAW-1
Honolulu International, Hawaii....................................................................... HNL-1
Wilmington International, Wilmington, North Carolina ................................... ILM-1
Shannon, Ireland ........................................................................................... INN-1
Diego Garcia NSF, Chagos Archipelago ....................................................... JDG-1
Yokota AB, Tokyo Honshu Island, Japan ...................................................... JTY-1
Koln/Bonn, Germany ..................................................................................... KBO-1
Kinshasa/N’Djili International, Zaire............................................................... KIN-1
King Khalid International, Riyadh, Saudi Arabia ............................................ KKI-1
Kennedy Space Center, Florida..................................................................... KSC-1
Lajes AB, Azores ........................................................................................... LAJ-1
Lincoln Municipal, Nebraska.......................................................................... LNK-1
Monrovia/Roberts International, Liberia......................................................... LRB-1
Orlando International, Florida ........................................................................ MCO-1
Moron AB, Spain ........................................................................................... MRN-1
Mountain Home AFB, Idaho .......................................................................... MUO-1
Grant County International, Washington* ...................................................... MWH-1
Myrtle Beach International, South Carolina ................................................... MYR-1
Cherry Point MCAS, North Carolina .............................................................. NKT-1
White Sands Space Harbor, New Mexico...................................................... NOR-1
Oceana NAS, Virginia.................................................................................... NTU-1
Leopold Sedar Senghor International, Dakar, Senegal ................................. OOY-1
Pease International Tradeport, Portsmouth, New Hampshire ....................... PSM-1
Tindal RAAF, Australia .................................................................................. PTN-1
Ellsworth AFB, South Dakota ........................................................................ RCA-1
Wake Island AAF, Wake Island ..................................................................... WAK-1
Wallops Flight Facility, Wallops Island, Virginia............................................. WAL-1
Halifax International, Halifax, Nova Scotia, Canada...................................... YHZ-1
Stephenville, Newfoundland, Canada............................................................ YJT-1
Nassau International, New Providence Island, Bahamas.............................. YNN-1
Gander International, Newfoundland, Canada .............................................. YQX-1
Goose Bay, Newfoundland, Canada ............................................................. YYR-1
St. John’s International, Newfoundland, Canada........................................... YYT-1
Zaragoza AB, Spain ...................................................................................... ZZA-1