Built in 1931. Listed on the National Register of Historic Places in 1985.
From the record
“The AJX Bridge is a historic Pratt truss bridge in southwestern Johnson County, Wyoming. The bridge was built in 1931 across the South Fork of the Powder River near Kaycee, Wyoming.”
Wikipedia article AJX Bridge over South Fork and Powder River, CC BY-SA 4.0.
One of 22 National Register listings published here for Johnson County · listed in 1985 · category: Structure · built in 1931.
Also known as. Vehicular Truss and Arch Bridges in Wyoming TR
Census division. Kaycee
When was it built? 1931
National Register reference number.85000426- the number the National Park Service assigned this property when it was listed, and the key its nomination file is catalogued under at the National Archives.
Fires near this property
12 since 1992
Regional context, not property-specific
evidence. The
federal wildfire occurrence database
lists 12 fires within 5 miles of AJX Bridge over South Fork and Powder River
between 1992 and 2018, burning about 401 acres in total. 7 started naturally. None was recorded as arson.
Distance is straight-line from the map coordinates, so a fire counted
here may appear on a neighbouring settlement's page as well.
Reported cause
Fires
Natural
7
Missing data/not specified/undetermined
5
The most recent of
them, most recent first, with the day each was reported and the service
that recorded it.
Regional context, not property-specific
evidence. The federal mineral resources record lists
21 workings within 5 miles of AJX Bridge over South Fork and Powder River: 16 occurrences, 4 unknowns, 1 producer.
1 still produces. What was taken out: Bentonite, Sand and Gravel, Construction. Distance is straight-line from the
map coordinates, so a quarry counted here may appear on a neighbouring
settlement's page as well.
Regional context, not property-specific
evidence. The National Weather Service names
Kaycee, the town this property stands in, in 43 storm reports between 1993 and 2025: 23 hail, 9 flash flood, 4 thunderstorm wind, 3 tornado.
No death or injury is recorded in these reports. Each account below is quoted exactly as the forecast office
filed it, from the NOAA Storm Events Database, and each date
opens the federal record of that event.
Heavy rain fell in the tributaries of the Powder River in southern Johnson and northern Natrona counties. The South Fork of the Powder River along with Salt Creek were two of the major contributors to a rapid rise in the water level of the Powder River near Sussex. High water on both the North and Middle forks of the Powder River also served to flood the main stem. The river climbed more than 10 feet in less than 24 hours at Sussex and crested at 15.63 feet around 0500MST on Monday, May 25. This crest topped the previous record crest of 15.16 feet set in May 1978. Agricultural land downstream of Kaycee near Sussex was completely inundated and several ranches and vehicles were surrounded by water.
Heavy rainfall estimated by radar to be 1 to 1.5 inches in less than 30 minutes inundated areas south of Barnum and into northern Natrona County. Blue Creek was flooded as were Poker Creek and some smaller streams feeding the Middle Fork of the Powder River. Several corrals were lost and damage was done to at least one out-building. One observer said it was the worst flooding they had seen in 27 years at their residence. Bar C Gap ran 6 to 7 feet deep and Bar C Ranch Road was covered with mud and debris.||Another hard hit area centered on Willow Creek and nearby drainages along the TTT-Lone Bear Road and West Willow Creek Road. Water was running over the roads in more than one location.
The North Fork of the Powder River flooded northwest of Kaycee as five inches of rain fell in about two hours. State Highway 191, Mayoworth Road, had water flowing both over and under portions of the road. Traffic was reduced to one lane on the road due to the flood waters. A ranch bridge was washed out and 300 bales of hay were destroyed.
NCRS reported the Middle Fork of the Powder River out of its banks in a few locations around Kaycee. The flooding was minor and no damage was reported.
A thunderstorm became severe as it moved off of the Bighorn Mountains as it approached Interstate 25. Quarter to golf ball sized hail fell along a line from Kaycee through Sussex, Wyoming.
A thunderstorm developed along the east slope of the Big Horn Range and become severe as it moved toward Kaycee and into Sussex, Wyoming. There were numerous reports of hail from quarter to half dollar size.
Heavy rain fell across southern Johnson County and brought flooding to the tributaries of the North Fork and Middle Fork of the Powder River. Flooding was observed between Mayoworth and Kaycee and also between Barnum and Kaycee.
Hail of one-half inch diameter to nickel size fell in Kaycee for 10 minutes. Also, at 1957MST an automated sensor recorded a wind gust to 57 mph at the fire hall east of Kaycee.
A thunderstorm in southern Johnson County produced a funnel cloud near the town of Mayoworth (36 miles south of Buffalo). Large hail was reported from this storm 10 miles north of Kaycee. Kaycee is located 44 miles south of Buffalo.
No historic map-sheet match is published
for this property yet. That does not mean no map exists. This record needs
a coordinate-quality review before it can be joined to a sheet boundary.
Browse the county's mapped places while that work is
pending.
Listing record. National Park Service National Register of Historic Places, listed-properties dataset, current to 2026-05-22.
Map join. Address geocoded through the United States Census geocoder, then tested against the published boundary of every sheet in the USGS Historical Topographic Map Collection.
How this page is made. Listing fields come from federal records; map-sheet coverage is a labelled coordinate-to-boundary calculation, not a source-field claim.
Wildfire. Short, Karen C. 2022. Spatial wildfire occurrence data for the United States, 1992-2020 [FPA_FOD_20221014]. 6th Edition. Fort Collins, CO: Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2013-0009.6 Collected with United States Government funding and usable without additional permissions or fees.
Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.
Storms. NOAA National Centers for Environmental Information, Storm Events Database https://www.ncei.noaa.gov/stormevents/ A work of the United States government, no copyright under 17 U.S.C. 105. Narratives are quoted verbatim from the National Weather Service report and are not edited or summarised.
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