Route 20 does not exist in Pokemon White, but does in Pokemon White 2.
There ins no route 20,there in just Kaspar Town. That acts as route 20.
There is no best route in Pokemon White 2 to find shiny Pokemon, because you have the same chance to find a shiny Pokemon on every route in the game.
You can't see it wild on Pokemon White but you can see it in Route 10, Route 11, Victory Road and Village Bridge on Pokemon White.
It's not on Route 4, it's in Route 9 during swarms and it's for Pokemon White only.
Route 3
sentret
Nest to route 5.
The PokeTransfer machine is in the PokeTransfer Lab on Route 15.route 15 is near black city (pokemon black) or white forest (pokemon white) and Marvelous Bridge
route 3
Poochyena can only be found on Route 9 on Pokemon white.
yes on route 18
catch it on route 1.