We went further south towards Lake Ngami

One of the picturesque sights in Botswana is the address system.  No road numbers exist (in fact no road names either).
  Description of where to turn off the road or track is given by "the old car door hanging in a tree"
 or "the green bucket with a tyre on a pole".  "BOY" above was certainly the best street address we saw.

After dropping in at "Swamp Stop" to see if we could spend the night there,
 we proceeded further south to Guma Lagoon. Swamp Stop is favoured by the overlanders
 and the British army and is not the place for "ballies"

Guma Lagoon is about 15 km off the road, and 11 km is through thick sand.
Landrovers and Landcruisers are the recommended mode of transport.

From here we went looking for Lake Ngami, but couldn't find it, so proceeded on to Maun.