And no let’s come to very bad part of Google Maps. I mentioned many roads with numbers of a nearby highway above, and that’s also true near Huai Nam Sai lake, https://www.openstreetmap.org/#map=14/7.8979/99.7955
Road Ns 4096 was missing completely in OSM, but a milestone showed that it is not a dead end: https://www.mapillary.com/app/user/bernhardhiller?lat=7.910547733055556&lng=99.78784179666667&z=17&pKey=MaUI-Bz36L9CRGse3uaDsg&focus=photo
Road 4270 was wrong in OSM and Google near the dam.
I decided to check that section of “4270” which leads into the forest in northern direction, just east of the dam: https://www.google.com/maps/@7.8953991,99.8145675,14.14z
It was missing in OSM.
It started as an asphalted road, but rather low quality. Shortly afterwards, the road was no more paved, but not so bad either: https://www.mapillary.com/app/?lat=7.905416011666667&lng=99.8141555786111&z=14.202209436577874&pKey=BV5BV2nZjynb2KZwXRjTDw&focus=photo
Steep section had concrete pavement, and steep it was: sometimes beyond 20%.
Eventually I reached the pass height, and went down on the other side. Then I found a school on the left side of the road, and the school roads were even paved with concrete (in the aerial images, you’ll see forest only): https://www.openstreetmap.org/node/7157425543#map=16/7.9206/99.8134
The road deteriorated terribly afterwards, cycling in the soft sand was not easy. When I arrived at an unmanaged ford, I decided to look at the aerial images of Google Maps, but … there is no phone connection available in that jungle.
Hence I returned to the junction where according to Google road 4270 ends. I asked a local man if I could get to Wang Hon on that road to the west, and he confirmed that.
According to Google Maps, road Ns 4096 was 5.2 km away and could be reached by normal car in 13 min - i.e. at an average speed of 25 km/h.
It started off worse than the other road, a very bad smoothness, and sections with concrete lanes (instead of full concrete pavement). Near the top, I missed the junction to road Ns 4096 and got stuck in a rubber plantation. Because the “road” to take leads down very steeply, and is not paved at all. You cannot do that by car, and with a 4WD you ought to have some experience also. I pushed my bike down.
That terrible way is to the left, and can hardly be seen on the photo:
https://www.mapillary.com/app/?lat=7.930521488055556&lng=99.80480957027777&z=17&pKey=7iFfxySFWXHmftjNVPRFog&focus=photo
Later on, it got better, and you can play with the images of these jungle roads I uploaded to Mapillary.
So take care when you travel with Google Maps on minor roads!