The pokéathalon dome is connected to the national park. If you enter the national park gate and go to the left, you will be at the pokéathalon dome.
you can find it a little after you leave goldenrod city.
there are no contests just a pokeathalon
Unfortunately there are absolutely no Pokemon contests in Heart Gold aside from the PokeAthalon.
In Pokeathalon, you need to get 3,000 points. But it will be available in some days.
By trading it while it's holding a metal coat. You can get a metal coat as a prize at the pokeathalon or you get it from some guy, but i can't remember who.
In any random place.Sometimes u need the dowsing machine.Sometimes in the Pokeathalon they are prizes for like 2000 points. You could cheat and get lots, but then again that's cheating.
I don't think there is one, but keep surfing and you might find it. If you know or have heard of someone who can make codes, request for them to make one.
Just go above Goldenrod to start. Then, before entering the National Park in the wide building, go to the left and up instead of just going up. There is the PokeAthlon, which is unlockable as soon as you enter it.
There is no best Pokemon on Pokemon HeartGold.
there is no Pokemon Mansion in Heartgold.
They are not in Pokemon HeartGold
where is the pokemon transfer lab in heartgold
No, but you can trade Pokemon only in HeartGold to Black