Explorers and pirates: Where can roads be built near undiscovered hexes?
There is no contradiction. A road is built between two hexes, hence it is adjacent to both these hexes. You can't build a road if one of these two hexes is undiscovered. You can build a road between two discovered hexes such that at the end of the road is an undiscovered hex; it's just that building this road doesn't "discover" the hex.