-



Living with a Garmin:

The Waypoints Limitation

Revised March 2009
Urban myth: portable 'leisure' GPS devices have insufficient waypoint memory to be really useful.
One problem is that 'Waypoint' is an umbrella term for several different types of 'point' - a point just being a pair of co-ordinates on the Earth's surface when all's said and done. Any documentation and discussion around this subject is usually insuffiently clear about which type of waypoint is being referred to at any given moment.

In particular, this article discusses three types of waypoint that are commonly uploaded into the GPS 'user' memory as part of routine everyday use. These are:
Routepoint - a point that is a constituent part of a Route. Also sometimes known as a Viapoint - but most people (including Garmin) tend to just refer to these points as 'Waypoints'.
User Waypoint - a point that is information-rich, with lots of added baggage in the form of data fields about that location. Most people just call these 'Waypoints' too.
A Routepoint may, or may not, also be a User Waypoint - and vice versa.
Trackpoint - a low-fat point that is part of a Track. These are generally called, er, Trackpoints.

It's hard to find the specifications for a Garmin GPS, all in one place, but with a bit of ferreting around you can come up with something like this - this is for a middle-of the range sort of device -
Etrex Legend Cx
Up to 500 Waypoints
Up to 50 Routes, of up to 250 waypoints each (off-road or direct routing mode)
In follow road or autorouting mode, a Route is limited to up to 50 waypoints
Up to 10000 Trackpoints
Up to 20 stored Tracks, of up to 500 Trackpoints each.
(NB that these limits have nothing to do with, and are not affected by, the size of any SD memory card that may be fitted.)

Now I'm going to rewrite that specification using clearer terminology, and then break it down line by line:
Etrex Legend Cx
Up to 500 User Waypoints
Up to 50 Routes.
A Route can have up to 250 Routepoints in off road mode or 50 Routepoints in follow road.
Up to 10000 Trackpoints for the Active or Recorded Track.
Up to 20 stored Tracks, of up to 500 Trackpoints each.

NB the above is just an example - some units have lower specs:
The Etrex C series can only store 20 Routes.
The Geko 201 and is limited to 125 Routepoints per route and 20 Routes, and can only store 10 Tracks.
Some have higher specs:
Most of the more modern units such as the Etrex H series, can store 1000 User Waypoints.

Now to break this spec down - what do these figures really mean?
The User Waypoints Limit (often 500, sometimes 1000) is the 'headline figure' that bothers some people. How can 500 points be enough? Well it's not enough (though 1000 may be) - but User Waypoints are not always the same thing as Routepoints.
It's possible (OK, maybe not easy) to stack a GPS full of Routes without using up a single User Waypoint.

The Routepoints Limit can now be seen in a more positive light. 50 Routes of 250 points totals 12,500 points - doesn't it? Well unfortunately not. You have to break it down, there is a -
Routes Limit (sometimes 20, sometimes 50) and a -
Routepoints Limit of maybe 125, more usually 250, in any one Route. None of these limits poses any real problem.
In follow road mode all Garmins can only handle 50 points in a route. But this is loads - most people probably only use about 10. And it does work best if these Routepoints are also proper User Waypoints.
There is a (unpublished) limit on Routepoint memory. Trials show that the total number of Routpoints is typically between 2400 and 5000 - it varies from model to model and to be honest unless you have the most basic of units you're most unlikely ever to encounter your limit, whatever it is.
In typical UK laney terrain and using direct routing mode, turn by turn, 100km will require about 100 waypoints, give or take. In remoter country such as mid-Wales or large parts of Europe, you would use far fewer points than this. So you can see that 2400 points is going to take you a very long way indeed!

If you want to explore the limits of your own Garmin GPS - how many points can it store - visit my Garmin Soak Test page, where there are a number of fully-loaded files for download.

The 10000 Trackpoints refers to the maximum number of points the GPS can record while you are travelling. This is called the Active Log. The factory setting is much lower than this but you can raise it to the max in the Setup Map menu. At default settings, it would take more than 24 hours continuous cycling to get to this limit. On reaching the limit the track either wraps or truncates - a menu choice - wrap is the better option.
So store your daily tracks (some models can do this automatically) and then clear the 'Active' memory daily.

The Tracks Limit (sometimes 10, more often 20) is the number of tracks you can upload to the GPS, or save from within the GPS menus, combined. So with a limit of 20 you could upload 5 and save 15 more. The Active Log is not included in this total. Nor are any tracks that have been stored onto the SD memory card. This is just the limit in 'user' memory.
The Trackpoints Limit is 500, in any one stored track (not including the Active Log, or tracks on the SD card). This is actually quite restricting - at default settings, 500 Trackpoints only represents about 30km of cycling. If you upload a track that is more than 500 points long, it just gets truncated. If you save a day's cycling, within the GPS - the 3000 or so points in your Active Log get downsampled to 500 - the track is all there but much rougher than you might have hoped.

Putting all this into perspective - a GPS loaded with a major project might look like this:
Lands End-John O'Groats, laney 1600km 17-day route:
38 user waypoints   basically one for each overnight, one for each midday stop
18 routes, totalling 1254 points   basically one a day
16 stored tracks, totalling 6753 points   basically one a day
and all this squeezed into a Legend C, an oldish model with no data card and limited memory by current standards.
This was a group ride, so the Routes and Tracks were just two alternative navigation methods - some people used one, some the other.

To put it bluntly -
All that is needed for Routes is Routepoints (especially if you are working in 'direct' or 'off road' mode), and
all that is needed for Tracks is Trackpoints.
User Waypoints are the better choice for Routes used in 'follow road' mode.

If you construct a on-road Route by 'joining the dots' using the Route Tool, in either Mapsource or Memory Map (and maybe other programs, I don't know) the points laid down are Routepoints. They are not User Waypoints unless one happens to coincide with a User Waypoint that has already been laid down.
In other software, the Route Tool may generate Routepoints that are also User Waypoints, I don't know.

See my other articles linked below, for more information on how to beat the Waypoints and Trackpoints Limits.

Francis Cooke

Footnote: Waypoint types: (NB - just my take on this confusing subject)

Waypoint is a generic term for a pair of co-ordinates in a wrapper of code. Usually there will be at least one other data field within the wrapper, which would be a unique Id or Name. There may or may not also be several other data fields, and see also 'User Waypoint' below.
The Waypoint is one of three top-level elements of GPS navigation, the others being the Route and the Track.
(NB that a 'point' is strictly speaking defined by 3 co-ordinates, not just two. Waypoints are however assumed to exist on a 2-dimensional plane, be it a map or the surface of the Earth. Altitude can be an added attribute, but is optional - if it's not supplied the 3rd co-ordinate is assumed to be the Earth's radius.)

Route is a term for a collection of Routepoints, listed in the order in which they are to be visited. (But NB that 'Follow Road' mode in the GPS can override this order and even disregard Routepoints altogether.) It is usually displayed as a (non-straight) line.

Track is a term for a collection of Trackpoints, listed in the order in which they were written. It is usually displayed as a (non-straight) line. It can be broken, consisting of one, two or more Track Segments which again are listed in order.
A Track is often produced by recording the progress of a moving GPS - sometimes referred to as a 'breadcrumb trail'.
Where a Track is drawn in software, one fundamental difference between a Track and a Route is simply the frequency, or the average distance between the points - Trackpoints would generally be less than 200m apart on average (usually much less, more like 50m or less), whilst Routepoints would generally be further apart than that (typically 1000m or more, on average).

Routepoint is my term for a Waypoint that is part of (ie contained in) a Route. (One implication of this is that the Name must be unique within that Route, but if there are 2 or more Routes, Routepoint Names need not be unique overall.) Routepoints are commonly just called Waypoints. Routepoints are generated by software that has a 'Route' tool or 'Create Route' option. The tool may or may not simultaneously generate User Waypoints (see below).
This is a common use of the term 'Routepoint' and it's how I use it in all these pages. However Garmin use the term 'Via Point' to describe this type of point, and they reserve 'Routepoint' to describe an intermediate point on a Route generated as part of an autorouting or 'Follow Road' process - in a Garmin GPX file these appear as GPXX or 'extension' points.

Trackpoint is a Waypoint but it doesnt even need a Name field. It can therefore be a very 'light' point. To be a viable point, it has to be part of a Track (or to be pedantic, contained in a Track Segment). Trackpoints are generated by any software that has a 'Track' tool or 'Draw Track' option, and more especially they are generated by a moving GPS as a 'breadcrumb trail'.

Via Point is another (and possibly more correct) name for a Routepoint.

Map Point is a point (not strictly a waypoint) that constitutes an element of a vector map. Like any other point, it can be information-rich and Garmin's system makes extensive use of this information to generate navigational hints. Garmin's Route Tool uses Map Points wherever possible, copying them in preference to generating new User Waypoints.
Obvious Map Points are things like road junctions, but they also exist on roads as intermediate points which are not obvious to the naked eye.

User Waypoint is my term to differentiate a (usually) information-rich Waypoint from all the other types listed above. User Waypoints are commonly just called Waypoints. They are generated by any software that has a 'Waypoint' tool, or on a live GPS by using the 'Mark Point' facility. Some software also generates them as a by-product of the 'Route Tool'. Garmin's Route Tool uses existing User Waypoints wherever possible, in preference to Map Points, but it will also generate a new User Waypoint if there is no pre-existing User Waypoint or Map Point that it can use (eg, when drawing a route across country). User Waypoints are usually displayed as a blob or dot, or assigned a symbolic marker such as a flag.

Gpoint is a term for any point displayed on, or part of, a Google Map.

POIs or Points of Interest are very similar to User Waypoints but are stored as named collections (such as 'Transport', 'Hotels', etc). POIs are embedded in some maps, each collection acting rather like a map overlay. POI collections can be downloaded from the Internet or generated using a free software tool supplied by Garmin. POIs are used extensively by the GPS 'Find' facility.

Geocaches are very similar to User Waypoints but with specific data fields that mark them out as Geocaches. They are used to mark the locations of 'buried treasure' to give people a raison d'etre for travelling with a GPS. There are several such locations within walking distance of where you live. Geocaches can be downloaded from the Internet, and the GPS has a special page to handle them.

Francis Cooke