NGS Commemorative Marks
NGS Commemorative Marks are survey monuments that have been set to celebrate significant anniversaries, events, scenic locations or for various other reasons. For example, Commemorative Marks have been set to:
- celebrate significant events such as NOAA’s 200th year anniversary,
- announce important accomplishments like a coral reef restoration,
- highlight the importance of a protected area, like a National Wildlife Refuge,
- and partner with other organizations, such as the Census Bureau Center of Population.
What is a Survey Mark?
Today, a typical survey mark or monument is a brass, bronze, or aluminum disk or rod. Previously, prominent objects like water towers or church spires were also used as survey monuments.
Hundreds of thousands of permanent survey marks can be found throughout the United States. These monuments have be placed by NGS, its predecessor agencies and other organizations since 1807. After each survey mark was set, surveyors would take measurements to ensure they accurately knew its location and elevation.
There are many reasons you need to know exact locations and elevations. You might use GPS to find out where you are going, or you might need a surveyor to help establish a property boundary. Accurate positions and elevations also help with the construction of buildings, bridges, and many other engineering applications.
Contact Us
Please contact us to request information on the NGS commemorative marks program, or any of the commemorative marks listed on this site.
