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--- facilities:military:cheyenne_mountain_complex [2026-04-04 21:15] – J. B. Crawford
+++ facilities:military:cheyenne_mountain_complex [2026-04-04 22:49] (current) – J. B. Crawford
@@ Line 5: / Line 5: @@
 As a result of improving technology (e.g. the Joint Surveillance System radar network and its multiple command centers) and changing threats (the transition from bombers to ballistic missiles), the military value of CMC declined starting in the 1970s, and functions slowly moved away. Although CMC is no longer a key military control center, it continues to receive some degree of maintenance and modernization as a secondary command center and training site for NORAD and USNORTHCOM.
-/* {{wst>location|38.7425|-104.848333}} */
+<olmap id="bigMap" width="100%" height="500px" lat="38.5" lon="-104" zoom="9" controls="1" baselyr="OpenStreetMap" kmlfile="facilities:military:cheyenne_mountain_complex:map.kml">
-<olmap id="olMap" width="100%" height="500px" lat="38" lon="-102" zoom="9" controls="1" baselyr="OpenStreetMap" kmlfile="facilities:military:cheyenne_mountain_complex:map.kml">
 </olmap>
+(You can {{ :facilities:military:cheyenne_mountain_complex:map.kml |download this KML file}})
 ===== Routes =====
 Because of CMC's importance as a military control center, and its hardened design, it had multiple redundant connections to AUTOVON and the general telephone network. These included microwave hops directly from north and south microwave sites, and two L-1 coaxial cables.
-CMC is sometimes described as having a "ring" of facilities around it for redundancy, a common strategy for both the military and AT&T. These facilities were not all coaxial; CMC's two coaxial cables connected it to one coaxial transcontinental and one microwave station. Microwave links would complete a ring.
 ^ Destination ^ Direction ^ Carrier |
@@ Line 22: / Line 20: @@
 | [[facilities/microwave/beulah|Beulah CO]] | | TD-2? |
 | [[facilities:radio:corral_bluff|Corral Bluffs CO]] | | TD-2 |
+==== "Ring" Network ====
+A [[https://coldwar-c4i.net/CMC/BLR1065/387.html|1965 BLR article]] describes CMC as surrounded by a ring of microwave sites for redundancy, called the "Close-in Automatic Route Restoral System." It's surprisingly difficult to match up this "ring" with known sites, perhaps beacuse of changes over the years. CMC is depicted in the article as having four coaxial cables and two microwave paths linking it to this ring. We know the two microwave paths (to Beulah and Calhan) and two of the coaxial cable (to Boone and Westcreek), but two of the cables remain unidentified. They head west from the site, rather than east like the other connections, at least if the simplified map is to be trusted.
+That said, the article says "eventually" and describes only two of the spokes as operational. That suggests that the two unexplained spokes may have simply never been constructed. Similarly, the outer "ring" routes may not have been completed, since the existing microwave sites do not quite form a ring.
+It is an interesting detail that CARRS is described as supporting 600 message channels and a two-way monochrome video channel.
 ==== Coaxial ====
-It's probably fair to say that CMC's "primary" telephone connection was the L-1 cable to the [[facilities/cable/lamar|Lamar, CO L-3I main station]] via [[facilities/cable/boone_l1_underground|Boone]]. The entire route of this cable can be traced via the repeater huts at 8 mile intervals. From the CMC, the L-1 cable runs generally south to Fort Carson's range area before turning east to cross the valley just south of Pikes Peak Speedway. The L-1 passes under the route of the transcontinental cable through Colorado, passes north of the Pueblo Transportation Technology Center, and then turns south to reach Boone. From Boone, the rought is east and slightly south until it turns southeast to reach Lamar. Most repeater huts on this route appear intact. There are one or two extra manholes along the route that may reflect later repair locations or something of the sort.
+It's probably fair to say that CMC's "primary" telephone connection was the L-1 cable to the [[facilities/cable/lamar|Lamar, CO L-3I main station]] via [[facilities/cable/boone_l1_underground|Boone]]. The entire route of this cable can be traced via the repeater huts at 8 mile intervals. From the CMC, the L-1 cable runs generally south to Fort Carson's range area before turning east to cross the valley just south of Pikes Peak Speedway. The L-1 passes under the route of the transcontinental cable through Colorado, passes north of the Pueblo Transportation Technology Center, and then turns south to reach Boone. From Boone, the rought is east and slightly south until it turns southeast to reach Lamar. Most repeater huts on this route appear intact. There are some manholes along the route for reasons I'm not sure of.
 At Lamar, the cable presumably also provided direct connections to the [[facilities/military/lamar_hf|Air Defense Command HF radio site]], "Operating Location Alpha Bravo," which is immediately adjacent to the Lamar L-3I station. This radio station may predate the L-3I cable.
@@ Line 31: / Line 37: @@
 CMC had a second L-1 cable that ran through the mountains to the [[facilities/microwave/westcreek|Westcreek, CO]] microwave station, where it terminated and exchanged traffic onto microwave routes. I have located one likely repeater on this route, which is of a different design than those on the route to Lamar but has the expected style of ROW markers on each side. The distance from Westcreek to CMC is small enough that no main power station was needed (like Boone on the other cable), but it should have 3-4 repeater huts along the way depending on the route the cable takes (the distance, as the crow flies, is about 32 miles).
-If my attempts at following the route are correct, the Westcreek cable follows a forest service road and then a ridgeline pretty much directly east from the Westcreek microwave site until it reaches CO 105, after which it heads southwest. After this point, the route gets a little more speculative---most of it is confirmed by both era-appropriate right of way markers and trenching scars in 1969 aerial photos, but there are multiple telephone cables in this area and I'm not totally sure I traced the right one. The spacing of the repeaters that I identified doesn't work out right, so likely at least one of them is wrong.
+The map here shows the route of the Westcreek cable as determined from 1969 aerial photos. Unfortunately, once the route reaches the area where Colorado Springs was built up by the 1960s, it is no longer easy to follow. The cable may enter ducts where it passes through developed areas, or may be buried adjacent to roads. Since most of Colorado Springs has received significant redevelopment since the '60s, few of the ROW markers remain in place.
-Aerial photos suggest that both cables were installed between 1960 and 1969, consistent with the original CMC project.
+The Westcreek cable terminated at very basic facilities in the Westcreek microwave site, and Flickr user Ashley And Co [[https://www.flickr.com/photos/ashleyandcompany/3744558618/in/set-72157621644|has some photos]] of that end.
 ==== Microwave ====