Skip to content


Earth is Round? Let's "correct" that

A cache by CartDaddy Send Message to Owner Message this owner
Hidden : 07/01/2009
2 out of 5
1 out of 5

Size: Size: not chosen (not chosen)

Join now to view geocache location details. It's free!


How Geocaching Works

Please note Use of services is subject to the terms and conditions in our disclaimer.

Geocache Description:

Have you ever tried to wrap a ball or other sphere? Trying to map a round earth has the same effect. This earthcache will take you out into the country to see how surveyors tried to overcome that effect.

Early in American history, the nation rapidly expanded its borders. A system was needed to map the land in an orderly fashion. The federal Bureau of Land Management established a system of surveys of all lands in the public domain.

While this system was effective in mapping out the land, it has an inherent flaw. Here in the northern hemisphere, meridians of longitude (the lines on the globe running north and south), all come closer together the further north you travel. Eventually, they all come together at the North Pole. While mapping large areas, the effect is subtle but noticeable. For this reason, surveyors had to use lines of correction, to “correct” for the curvature of the earth.

Different methods were used, but a common practice was to use a principle meridian, then correct for earth’s curvature every 24 miles east and west from principle meridian. This kept the curve’s effect to a minimum. Lands were divided into six-mile by six-mile townships, and meridians were corrected every four townships, or 24 miles.

The town of Correctionville took its name because it lies on a line of correction. The given coordinates for this earthcache will take you to a country road. Be sure to pull well off Highway 20. The side road you are on is a dead end road so traffic shouldn’t be an issue here. To receive credit for this earthcache do the following:

1. While at this location, mark on your GPSr this coordinate: 42N 28.483 95W 44.869. Now measure the distance from where you are to the coordinate just entered. This is the distance surveyors had to “correct” for earth’s curvature in this area. Send me an email with the distance you came up with.

2. Proceed west to Correctionville to 42N 28.493 95W 47.144. Here you will find a sign in the middle of town commemorating the line of “correction” that runs through Correctionville. Take a picture and post it with your log. The picture should contain members of your group and the sign, and be creative!

Additional Hints (No hints available.)

Reviewer notes

Use this space to describe your geocache location, container, and how it's hidden to your reviewer. If you've made changes, tell the reviewer what changes you made. The more they know, the easier it is for them to publish your geocache. This note will not be visible to the public when your geocache is published.