Is there a document or manual that clearly explains the different methods of routing

What 'each option does' is more to do with the map being used rather than the other options. Any guide therefore as to specifically what each routing and road type will do wouldn't really be worth much.

I have Road cycling – I guess it only uses a road ===>>> paved roads (ignoring road speed) ==>>> riding a road (racing) bicycle.

Tour Cycling – what is the difference from Road cycling ===>>> like road cycling but prefers cycleways (and routes marked for more "liesurely" riding).

Mountain Biking – I take it will use off road tracks. ===>>> Unpaved/dirt paths suitable for mountain biking (which you might want to avoid if not using a MTB).

Automobile driving. ===>>> Include motorways (roads that bicycles are not allowed on). Likely prefers faster roads.

Motorcycle driving ===>>> include "curvy" roads (this also might deemphasize roads with low speed limits). This is for motorcycling as a sport (not transportation).

Pedestrian ===>>> includes ways marked as "pedestrian only" and footpaths (walkways). Excludes motorways. Doesn't care about road speed.

Direct routing – I guess won’t follow routes but straight to way points. ===>>> For hiking in places where you are using paths that aren't on the map (this is basically the "no routing" option.

I'm surprised the 820 offers all these options.


How well any of these work (especially, the less usual ones) work depend on the data encoded in the map you are using. The 820 (and the 1000 and Touring) use Openstreetmap (OSM) maps.

Road classes (motorway, trunk, primary, secondary, tertiary, other) are enough to make assumptions about speed (and some other stuff).

Route creation basically tries to find the shortest route using the set of roads/paths that are not excluded or that have attributes you are avoiding (like toll roads).

Keep in mind that the on-device routing can produce routes that have issues. You might get more predictable results planning a route on something like Garmin Connect or ridewithgps and use the tcx/gpx track file they produce.

Then I have default ride type:

Road
Mixed surface
Mountain
Gravel
Commuting
Cyclo cross
Indoor
eBike
eMountain.

This is just the type bike you are using. It's just a way of organizing your rides.

What 'each option does' is more to do with the map being used rather than the other options. Any guide therefore as to specifically what each routing and road type will do wouldn't really be worth much.

This doesn't improve people's understanding.

The map data certainly matters but the different routing options will do different things on any map people are likely to use.

Yes agreed. But the point I was making, possibly badly, was that it'll vary depending on the map, so it's really impossible to state with any accuracy exactly what each will do.

Peligro agen

...was that it'll vary depending on the map, so it's really impossible to state with any accuracy exactly what each will do.

Even with that, it's important to pick the appropriate routing type, especially for cycling.

Even without being accurate, there might be options that are more preferable.

Most maps have motorways encoded the same way and cyclists (in general) can't use them. So, if one is cycling, it make sense to avoid using the routing for motor vehicles.

Faster road cyclists might not like the routes produced by the touring option.

One big problem is that cyclists have different opinions about what is a good road for cycling.

In any case, one should be careful to look at the route the device calculates.

I believe that Tour Cycling will use Cycle Lanes whereas Road Cycling will not.

Thank all - at least I have some more information now.

I have played a little more with the routing and indeed road cycling and tour cycling give slightly different routes – interestingly, I tried it for car navigation by selecting automobile driving – don’t do this, it seems to want to take you down interesting routes and not direct routes. It added 30 miles onto a 60 mile route and 7 miles onto a 30 mile route compared to my NUVI – it got me to the destination but have no idea why it took me the way it did. Anyway I am happy with the cycling routes.