Garmin 24k topo vs OSM / others?

Just picked up a 66i to use while hiking in the USA and I’m looking to add some better maps. I’m curious how much, if at all, better the Garmin 24k maps are than various free ones like OSM? What do I gain for the $100? Thanks!

0 twolpert over 5 years ago

As the name implies, the 24K maps are 1:24000. The OSM topos for the USA are approximately 1:34000. I do not know how elevation is represented on the Garmin 24K maps. They claim to be comparable to USGS topos, which would typically mean variable contour spacing depending on location. The OSM topos are based on standard DEM data. They claim to show 50 foot contour lines everywhere, with 250 foot major contour intervals. Some of the illustrations do not support this. Although the OSM topos are not updated as frequently as other OSM maps, they are likely to show more up to date information than the Garmin 24K maps. How much more up to date is an open question.

I don't know how they compare as far as trails, trail heads, parking, and so forth.

Reference for TopoOSM: https://wiki.openstreetmap.org/wiki/TopOSM

0 camhabib over 5 years ago in reply to twolpert

Unfortunately, the thing I am most concerned about isn't the elevation but rather the trail locations, etc. My experience with the 100k Garmin maps has been less than great as far as accuracy, and was hoping to get a set of maps that improved on that. I have a very old set of 24k maps on an SD card, and I know for the area I primarily hike, a lot of the trails have changed since the version I have was released.

0 twolpert over 5 years ago in reply to camhabib

If you're mostly interested in trails, you might check out the normal OSM maps for your area. Even the standard OSM maps frequently show trails. They are, of course, crowd-sourced - so the quality and timeliness varies considerably. If you are actually interested in routing, you should check that independently.

Personally, I usually look for a recent track in the area rather than relying on seeing the trail on the map. OSM includes some of that, without much in the way of details. There are a lot of crowd-sourced sites which have good tracks - some free, some paid, and some freemium. You might also check out gpsfiledepot to see if there are custom trail maps for your area.