United States

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The spire of the Fair Haven, Vermont First Baptist Church is a horizontal survey mark (triangulation station) and is described in the NGS National Spatial Reference System under the permanent ID OD1373

The United States National Geodetic Survey (NGS) and predecessor agencies manages the National Spatial Reference System (NSRS), which includes permanent survey marks for horizontal position (latitude and longitude), height, or gravity. Some marks have information for both horizontal position and height. Some marks were established by NGS. Others were established by other organizations, such as state highway departments, but are included in the database that makes up the NSRS. Information about marks is available to the public online. The number of points in the NSRS is over 1,500,000.[1]

Works cited

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  1. ^ "What is the National Spatial Reference System?". National Geodetic Survey. 28 October 2019. Retrieved 1 December 2023.