If wanted, you may provide a name to a Geohash location, by appending the name to the Geohash itself after a colon. Any underlines in the name will be replaced by spaces, and the name will be displayed in geohash.org, and also used as the default title for GPX downloads and when sending it to Garmin GPS receivers. Here is an example:
http://geohash.org/c216ne:Mt_HoodGeohashes offer properties like arbitrary precision, similar prefixes for nearby positions, and the possibility of gradually removing characters from the end of the code to reduce its size (and gradually lose precision).
As a practical example, the Geohash 6gkzwgjzn820 decodes to the coordinates -25.382708 and -49.265506, while the Geohash 6gkzwgjz will decode to -25.383 and -49.266, and if we take a similar position in the same region, such as -25.427 and -49.315, we can see it being encoded as 6gkzmg1w (note the similar prefix).
For a detailed explanation of how a Geohash are encoded and decoded, check the Wikipedia article about it.
If you use Google Maps, there are a few ways to easily generate a Geohash for a given location.
The most trivial way is to bookmark the following link: Geohash from Google Maps. Then, whenever you're looking at a map, clicking on the bookmark will open geohash.org with the point in the center of the map.
A perhaps more convenient way is to use the Geohash Mapplet for Google Maps. When enabled, it shows a marker that may be dragged to any point in the map to obtain the Geohash for the given position.
When buildilng custom queries for geohash.org, there are a few additional parameters that you may use depending on your needs.
The format parameter allows you to redirect directly to the given format. As an example, the following URL will redirect the browser directly to the GPX download page:
http://geohash.org?q=45.37,-121.7&format=gpxThe redirect parameter allows preventing geohash.org from redirecting to the Geohash URL, and instead showing content in place. The following, for instance, shows the Geohash URL for the given query as textual content:
http://geohash.org?q=45.37,-121.7&format=url&redirect=0The following formats are currently available:
— open the location in OpenStreetMaps
— open the location in Google Maps
— go to the nearest geocaches in Geocaching.com
— go directly to GPX download page
— go directly to Garmin download page
— show coordinates as plain text
— show Geohash URL as plain text
— maximum length of the Geohash