td = TravelDirections[{Entity["Building",
"EmpireStateBuilding::h583b"],
Entity["Building", "GrandCentralTerminal::xyg9f"]}];
points = Union[
Cases[td["TravelPath"] /.
GeoPath[GeoPosition[a_], "TravelPath"] -> a, {_, _}, {2}]];
combo = Flatten[
Table[{points[[i]], points[[j]]}, {i, Length@points - 1}, {j,
i + 1, Length@points}], 1];
last = SortBy[{GeoPosition[Mean[#]], #,
EuclideanDistance[#[[1]], #[[2]]]} & /@ combo, Last] // Last;
GeoGraphics[{GeoPath@td,
GeoDisk[last[[1]], 0.5 GeoDistance[Sequence@last[[2]]]]}]
