Measuring the World
A History of Datums in America, Part 2: NAD 83, HARN, NAVD 88, and the GPS Era
How NAD 83 evolved through the 1986 adjustment, 83/90-era networks, HARN, FBN, CORS96, NSRS2007, and NAD 83(2011)—and how NAVD 88 replaced NGVD 29.
From the Index
Tag: Series: A History of Datums in America
A connected two-part history of American survey datums. Reading order: Part 1 (post 621), Part 2 (post 622).
Measuring the World
A History of Datums in America, Part 1: From Colonial Surveys to NAD 27 and NGVD 29
From colonial metes-and-bounds surveys and Mason and Dixon to the Coast Survey, U.S. Standard Datum, NAD 27, State Plane coordinates, and NGVD 29.