Legends way back . . . at that time I had oh . . . 10-15 city maps that I had offered. The city maps have since been expanded, some suburbs & rural, a river set, some rolling hills, a few mountain maps and a mash up of CBT maps.
The last is why I was asking if they were official since I was trimming 2x2 of like CBT maps into a single 32x32 hex map. It let me specifically make about a dozen CBT maps and provided easy templates to alter. For instance I took the rolling hills combination map and made variations-
One has a E-W creek that will link up with other E-W creek maps. One has half that E-W creek map but curves it to S to create a turn. One has a N-S creek. One has turns that creek (either N-S or E-W) into a pond.
Ditto with roads, instead of one having the pond it has a town. Or it has a refueling point on the long road.
The whole point was to create a integrated set like a puzzle where you can combine 3x3 or 4x4 of the 32 hex maps where roads, rivers and other features work coherently from one specific map to the next in a effort to 'hide' the borders between each map.