GPX

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What is GPX?

GPX stands for GPS Exchange Format. It allows people to exchange data about:

Geocachers use GPX files to download cache coordinates into their GPS receiver. This saves the hassle of entering coordinates of each cache into their GPS receiver.

The normal process it to download waypoints from a cache listing website into waypoint management software on your PC, and then download the waypoints into your GPS.

GPX was developed by Topografix, which publishes the GPX format specfication.

Different GPX formats

GPX defines the method of storing waypoints, but it doesn't define the method of storing the additional information you need to store for a cache, for example it's terrain and difficulty.

Groundspeak developed extensions to cover this information, however unfortunately they have made the extensions proprietary so they cannot be used by other cache listing websites. Geocaching.com makes their GPX files available to Premium members via a method called Pocket queries.

Geocaching Australia has therefore needed to develop its own GPX extensions. These are incompatible with the Groundspeak extensions, however they are non-proprietary. GSAK supports them all.

The Geocaching Australia extensions are being supported by new software. The current status is listed under waypoint management software.


Obtaining GPX Files

GPX files are available from a number of sources.

Geocaching.com Pocket Queries

The first is through Pocket queries (or PQs for short) on Geocaching.com. This is a Premium member service on that website. A Pocket Query is only going to provide geocaches that are initially listed on that site. It will give you a large part, but not necessarily the whole picture of geocaching in your area.

Geocaching Australia GPX files

The second method for obtaining GPX files is from Geocaching Australia. This will give you state-by-state GPX files for caches listed on Geocaching Australia only. These files are available on each state page of caches and are also linked directly below.

GPX links by state :



Geocaching Australia My Queries

The new My Query feature on Geocaching Australia is a query generator which allows pre-defined queries:

  • private to individual cachers; or
  • publicly available to all cachers.

My Query generated GPX files can also be emailed to you on a regular basis. Set up a My Query, add the day of the week you want and, if appliable, an alternative email address to the default one you use at GCA.

Around 1:00am on the morning of choice a ZIP GPX file will be emailed to you containing the results you are after.

Geocaching.com GPX Files

You must join geocaching.com and pay a membership fee to obtain GPX files from the Groundspeak geocaching.com site.

Loading Geocaching Australia GPX files to Garmin Colorado and Oregon

You can use the "Send To" link on any Geocaching Australia cache page to send a complete geocache to your Garmin Colorado or Oregon.

As Groundspeak have intellectual property rights to the groundspeak namespace, you cannot load a GPX file directly from Geocaching Australia to your Garmin Colorado or Oregon.

You can, however, transform the GPX file through an alternative program like GSAK which will prepend the groundspeak namespaces as necessary.

After some discussion in the forums, some further transformation may be necessary.

After some investigation I found that GCA caches have no "groundspeak:cache id" tag. This tag is what the Oregon uses to check for uniqueness of caches. A simple GASK macro is all that was requires to change this value within GSAK. Once exported everything works properly with all GCA caches now displayed: 

$NewCode=0
$NChar=0
MFilter Expression= Left($d_code,2)="GA"
GOTO Position=Top
WHILE NOT($_EOL)
$Length=Len($d_Code)
$DropCode=Right($d_code, $Length-2)
$NewCode=val($DropCode)
$NewCode=90000000 + $NewCode
$d_CacheID = "$NewCode"
$NewCode=0
GOTO Position=Next
ENDWHILE
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