Great Circle Mapper

This is the second in a series of posts on travel-related websites. The previous post focused on TravelMath.com, while this post is about a fun mapping app, Great Circle Mapper.

In a previous post, I shared about TravelMath.com, a research site for travel. In the post, I used examples of a few cities in the United States that share names with much larger cities around the world. A few examples with the closest airport (using Travel Math) and their sister cities are listed here:

• Athens, Georgia (AHN) - Athens, Greece (ATH)
• Paris, Texas (PRX) - Paris, France (CDG)
• London, Kentucky (LOZ) - London, England (LHR)
• Hamburg, Iowa (OMA) - Hamburg, Germany (HAM)
• Venice, California (LAX) - Venice, Italy (VCE)

I first discovered these sites while creating a route map. I wanted to show direct flight paths between each city of origin and the destination city for a business conference. Several data mapping sites exist, but this one seems to focus more on airport and flight information.

Great Circle Mapper

According to the FAQ on the website, the primary purpose of the Great Circle Mapper is to display maps depicting the great circle path between locations and to compute distances along those paths. A great circle path is the shortest path on the surface of a sphere between two points on that sphere. Technically, the term geodesic path should be used since Earth is not a true sphere, but the great circle terminology is common usage.

I like website that get right to the point, and this is one of those. At the top of the screen is a space to type in your airport information.

Using the airport information listed above, I typed in the following:

ahn-ath, prx-cdg, loz-lhr, oma-ham, lax-vce

The result was a map of the world depicting my origin and destination points. There are four basic map available: plain, light, Facebook, and blue marble.

A variety of display options are available. For example, it is possible to display various airport information from the three letter code to city, state, and country data.

The scale of the map is determined by the starting and ending points. If you map between two airports in New York, just that region of the country will be displayed. When you map several domestic (US) points, most of the United States will display.

Additionally, you are not limited to direct flight paths. After creating the maps above, I entered in new airport information:

ahn-prx-loz-jfk-oma-lax

The resulting map is below. This is probably neither an efficient nor desirable route, but serves the purpose of illustration.

Have fun mapping!