What is July 18, 2026?

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Do you know the value of this date, without a Google Search?

Surveyors are supposed to "Follow the Footsteps of the Original Surveyor", but how many of you actually know the history and value the history of land surveying and the infrastructure of California?

Maybe a quick search of the Mount Diablo Surveyors Historical Society (MDSHS.org) will help? Are you a history buff, and not a current member of the MDSHS, why not? We have a new website online with additional information coming soon, so save the link! Members recently made the trek up the summit and initial point for some fresh new photos coming soon from ground and air (drone)!

July 18, 2026 the Mt. Diablo Surveyor’s Historical Society (MDSHS) in conjunction with the CA State Parks is hosting the 175th Anniversary of the setting of the Mt. Diablo Initial Point by Col. Leander Ransom, and we invite you to come join us for a day of celebration! There will be a display at the Upper Parking Lot, at the Summit Visitor Center and initial point.

Come learn about the 3.5’+/- difference between the two documented initial points, established by Ransom (General Land Office) in 1851, then followed up in 1852 by R.D. Cutts (Coast Survey). John Pettley who discovered this during his senior project while attending CSU Fresno will be on hand to answer any questions.

So mark your calendar now, and SAVE the Date: July 18, 2026!!! Come join us, MDSHS from 10AM – 4PM at the Mt. Diablo Initial Point and celebrate 175 years of its establishment for mapping most of California and all of Nevada Public Lands.

https://mdshs.org/

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Colonel Leander Ransom established Mount Diablo as the initial reference point for
public land surveys for California & Nevada in July1851.
A Celebration is being planned & co-sponsored by Mt. Diablo State Park
and Mt. Diablo Surveyors Historical Society.
July 18, 2026, at the Summit from 10 am to 4 pm,
Mt. Diablo State Park,
96 Mitchell Canyon Road, Clayton, CA.

PLEASE SIGN UP TO VOLUNTEER! Shifts of 2 hours are available. We expect the public and land surveyors to come out to enjoy the view and the history!

Here's the link to sign up
https://docs.google.com/forms/d/e/1FAIp ... usp=header

Historical Exhibits & Hands on Activities
Educational Exhibits on the Public Lands Survey System
Demonstrations of Old and New Surveying Activities
For the enjoyment & edification of the Public
As well as Old(er) and New(er) Land Surveyors
You are invited to Attend and to Participate at this Historic Event!
Volunteers and Sponsors Needed!!
See flyer attached.
https://www.mdshs.org
e-mail mdshsorg@yahoo.com for more info.
Stay connected!
Follow us for more news and updates at
@mdshs1851
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