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Details for Benchmark: HT3379

N 37° 55.431 W 122° 35.798 (NAD 83)

Altitude: 2562

Coordinates may not be exact. Altitude is SCALED and location is ADJUSTED. (more info)

Location:
In MARIN county, CA View Original Datasheet
Designation:
MOUNT TAMALPAIS RAD DOME
Marker Type:
spherical radome
Setting:
setting not listed - see description
Stability:

Must Read!

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Hard to miss on a nice clear day, especially while wandering the peaks.

It was too foggy to get this while we were at the Lookout or in the area on the mountain yesterday, so had to get it today from the road.

[Photos:]
photoHT3379: Mt. Tamalpais Radio Dome [on L]

Found it while visiting Mount Tamalpais's East Peak.

Backlogging all the benchmarks I have previously found. Sorry for the inaccurate log dates!

RAD DOME was not accessible, gate locked, however the dome can be seen from both the West and East Peaks.

[Photos:]
photoIMG_5939
seen from the Old Air Force Station – West Peak
photoIMG_5956
viewed from Garner Lookout, East Peak; far hill in center

Found with shell1fish.

Saw while driving to Mount Tamalpais East Peak. The dome seems to be in good condition.

[Photos:]
photoMOUNT TAMALPAIS RAD DOME - HT3379 from East Peak
photoMOUNT TAMALPAIS RAD DOME from Ridgecrest Blvd

Passing by.

Pretty weird looking tower. On the way down, I noticed it has a red light on top that I hadn't noticed earlier.

I got to visit this site when it was still an operational early warning radar station.

The golfball on Tam's belly
Is visible from miles around
But today I only log it
Because I was on its shadowed ground

Visited the Radar station below (padded in the pool!)
Waterweasel recalls being IN the dome when it was operational.
It certainly is a Marin Icon!

[Photos:]
photoYou can see it for miles and miles and miles

Found while visiting the Stinson Beach area for Thanksgiving weekend.

[Photos:]
photoHt3379 in the background.
Yes, it is there!

Sotted from all the over at the Sutro Baths today.

[Photos:]
photoRadar Dome

Found as described

All I have to say is woah!

You can only get so close to this one, but it's cool to see.

Spotted during our windswept mini hike today

Very cool benchmark, almost like something from an old sci-fi movie. I need to start an album of all the unusual ones like this.

Saw it as we hiked to/from breakfast.

(T: 1133) Yep. A big ball. BKip

[Photos:]
photoHT3379, Mt Tamalpais State Park, CA

looks like a sports ball up close!

This one was another easy find as it can be seen from miles away.

Not very white with the sun behind it to the west but still a dome.

hard to miss.

It looks like a big white golf ball sitting atop the west peak of Mt. Tamalpais.

Documented History (by the NGS)

01/01/1962 by CGS (FIRST OBSERVED)
DESCRIBED BY COAST AND GEODETIC SURVEY 1962 (IRR) THE STATION IS LOCATED ON THE TOP AND HIGHEST POINT OF THE WESTERN AND HIGHEST SUMMIT OF MOUNT TAMALPAIS, AIRLINE ABOUT 3 MILES NORTHWEST OF MILL VALLEY, AND IS THE CENTER OF A SEARCH RADAR DOME, THE EAST AND HIGHEST ONE OF TWO SIMILAR DOMES ON THE SUMMIT. THE DOME IS WHITE, 50 FEET IN DIAMETER, SETS ON TOP OF A 46-FOOT SQUARE, 50-FOOT HIGH, STEEL TOWER, THE TOP HALF OF WHICH IS ENCLOSED, AND IS ABOUT 85 FEET HIGH.
01/01/1976 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1976 (CA) RECOVERED BY AZIMUTH CHECK. AIRLINE DISTANCE AND DIRECTION FROM NEAREST TOWN 3 MILES NW OF MILL VALLEY.
01/01/1977 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1977 (CA) THE STATION WAS RECOVERED AS DESCRIBED BY I.R.B. IN 1962. AIRLINE DISTANCE AND DIRECTION FROM NEAREST TOWN 3 MILES NORTHWEST OF MILL VALLEY.
01/01/1978 by NOS (GOOD)
RECOVERY NOTE BY NATIONAL OCEAN SERVICE 1978 (JPR) THE STATION WAS RECOVERED IN GOOD CONDITION AS DESCRIBED. DESCRIBED BY S.M. MILLER
01/01/1980 by NOS (GOOD)
RECOVERY NOTE BY NATIONAL OCEAN SERVICE 1980 (DRT) RECOVERED AS DESCRIBED. DESCRIBED BY D.D. SMITH
01/01/1981 by USCG (GOOD)
RECOVERY NOTE BY US COAST GUARD 1981 (MEF) THE STATION WAS RECOVERED IN GOOD CONDITION.
01/01/1986 by USPSQD (GOOD)
RECOVERY NOTE BY US POWER SQUADRON 1986 (MIH) RECOVERED IN GOOD CONDITION.

Control Text

  • The horizontal coordinates were established by classical geodetic methods and adjusted by the National Geodetic Survey in March 1994. The horizontal coordinates are valid at the epoch date displayed above. The epoch date for horizontal control is a decimal equivalence of Year/Month/Day.
  • The orthometric height was scaled from a topographic map.
  • The Laplace correction was computed from DEFLEC99 derived deflections.
  • The geoid height was determined by GEOID99.

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