you can not go undergrond
You can't get to Route 214 in "Pokémon HeartGold" because there is no such thing as Route 214 in "HeartGold."
You can only catch Vulpix in SoulSilver, not in HeartGold. You can catch it on route 36 and route 37.
its on route 26
Route 214 isn't in Pokemon HeartGold.
You can get Mareep on route 32 and flaffy on route 43
Yes you can at route 1
route 25
route 32
In Pokemon HeartGold (And Pokemon SoulSilver) The bike road is on Route 17 in the Kanto region.
his house is on the route above cherrygrove
it is not on route 18
Yes, you can on route 32, route 42, and on route 43.