Yellowstone Benchmarks From the North: Reset your odometer/gps at the Roosevelt Arch From Mammoth Hot Springs: Reset your odometer/gps as you pass the Mammoth Post Office heading north Most of the benchmarks along this section are a mixture of those installed by the Bureau of Public Roads in 1923 and the U.S. Coast and Geodetic Survey in 1960. There s one interesting cast-iron NPS marker from an unknown date (but believed to be from the late 1910s). If you elect to go looking for the CORS station east of the old school, understand that you re entering a residential area. Park at the school and walk back to the station s location.
PID: QX0584 Stamp: D 565 1983 Family: Y Access: N Ease: E Coordinates: 45.0295100-110.70837 Elevation: 5318.45 Mon Date: 1983 Responsible Agency: NGS To Reach: South & east of Roosevelt Arch, in 3x3 ft exposed bedrock, 76 ft E of the center of the archway, 47 ft NE of road centerline. PID: QX0585 Stamp: E 565 1983 Family: Y Access: N Ease: E Coordinates: 45.02079-110.69647 Elevation: 5357.41 Mon Date: 1983 Responsible Agency: NGS To Reach: 0.85 miles S of Roosevelt Arch on, at SE end of paved pullout with interpretive display on the Northern Range, in 3x3 ft exposed bedrock, 22 ft E of E edge of interpretive display sign PID: QX9902 Stamp: 19 Family: N Access: Y Ease: E Coordinates: 45.01125-110.69426 Elevation: 5455.00 Responsible Agency: BPR To Reach: 1.65 miles S of Gardiner on, in N end of E walkway on bridge over Gardner River. NER-2
PID: QX0116 Stamp: G 162 1960 Family: N Access: N Ease: E Coordinates: 45.01093-110.69408 Elevation: 5427.03 To Reach: 1.65 miles S of Gardiner on, in S end of E walkway on bridge over the Gardner River. PID: PY9906 Stamp: 58 Family: N Access: Y Ease: E Coordinates: 44.99341-110.69328 Elevation: 5699.00 Responsible Agency: BPR To Reach: 2.25 miles N of Mammoth Post Office, on the bridge over the Gardner River. At the NW end of the W walkway of the bridge N of the Boiling River turnout. PID: PY0155 Stamp: J 162 1960 Family: N Access: N Ease: E Coordinates: 44.99324-110.69303 Elevation: 5632.89 To Reach: 2.25 miles N of Mammoth Post Office, on the bridge over the Gardner River. In the NW end of the W walkway of the bridge N of the Boiling River turnout. NER-3
PID: PY0156 Stamp: X 8 5631.590 Family: N Access: N Ease: E Coordinates: 44.99235-110.6922 Elevation: 5635.82 To Reach: 2.2 miles N of Mammoth Post Office, set off E side of road, 200 ft S of the entry road for the Boiling River parking lot, on a concrete post. Requires walk down steep slope. PID: PY0158 Stamp: 15 Family: N Access: N Ease: M Coordinates: 44.98084-110.69174 Elevation: 5942.06 Mon Date: Unknown Responsible Agency: NPS To Reach: 1.25 miles N of Mammoth Post Office, 132 ft W of road centerline, 0.2 mi NE of Mammoth Campground. Green metal post next to small USDI marker. Park vehicle in gravel turnout across from Lava Creek Trailhead, and hike 420 ft N along summit of hill. You ll see the short green post out in the field to your left. PID: AI5647 Stamp: N/A Family: N Access: N Ease: E Coordinates: 44.973447, -110.689289 Elevation: 5985.05 Mon Date: 1998 Responsible Agency: UNAVCO/PBO To Reach: 0.9 miles N of Mammoth Post Office, turn E into residential drive, then into old school parking lot. Walk approx 300 ft E of school to earthen vault with Seismic Station sign on door. Station is on hill above vault. NER-4
PID: PY0159 Stamp: B 157 1960 Family: N Access: N Ease: M Coordinates: 44.972022-110.694254 Elevation: 6062.06 To Reach: 0.55 miles N of Mammoth Post Office, 58 ft from road centerline inside the hairpin curve just before you enter the curve. PID: PY0160 Stamp: Y8 1923 6239 Family: Y Access: Y Ease: E Coordinates: 44.976365971-110.699768 Elevation: 6243.78 To Reach: Located on small concrete monument right in front of Albright VC next to walkway NER-5