[time-nuts] Averaging Location for Position Hold

Hal Murray hmurray at megapathdsl.net
Wed Sep 14 05:47:40 UTC 2011

> Often, you can talk to the local city/county and find out where some
> accurate benchmarks are, typically on a curb.  They are used to define
> street positions and such. 

I'm in Menlo Park.  The USGS has a big office complex here.  That includes a 
bench mark just outside the front door of the main public building (map 
sales, talks, bureaucrats, ...).  There may be a better one out near the 
flagpole.  (It's out of the shadow/multipath of the building.)

I'd expect there would be an on-line database of that sort of thing.  Anybody 
know a good URL?


Google blundered into this, but I haven't checked much:
They have lots of records that aren't interesting but also a category of "US 
Benchmarks" that may be an interesting subset.

While hiking, I've seen benchmarks by CA Highways (I think) so "USGS" may be 
overly restrictive.

These are my opinions, not necessarily my employer's.  I hate spam.

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