snowpoint city, the battle zone (you can battle him on weekends) and stark mountain.
To get to Snowpoint City you have to beat the Canalave City Gym Leader and then your rival will rush up to you and take you to the the top floor of the library. Professor Rowan will blab on about legendary Pokemon and stuff, and tell you to go to lake Valor. Beat the Team Galactic Grunt team members there then go to Lake Verity and beat Galactic Commander, Mars. Then Professor Rowan will ask you to up to Snowpoint City because he is worried about your rival. To get there you take Mt Coronet Path upwards from Celestic Town left route.
after u beat the 7th gym leader go back to veilstone city and get the storage key of the team galactic guy standing outside the big headquarters he drops the key then u go into the warehouse and get the galactic key
Spear pillar, which is at the top at mt.cornet. There you can catch dalgia.
They are at Velstone City again. Then you go to Mount Corenet from route 207 then go to Spear Pollar which is at the top of Mount Corenet then you beat team galactic.
after you get galactic key go to the HQ with sattilite dish go to the door
keep on going east and follow him
you have rock climb now, go meet your rival at lake acuity. then afterwards, go to veilstone city and go to the team galactic HQ
Sunyshore city. Beat volkner and go and beat the E4!
you go to velistone city and beat team galactic.
after talking to your rival go to the galactic HQ and talk to the guy looking at the antennae
You go to acuity lake
you go to sunyshore city and beat the gym leader
you need to go to the other side after you beat the game
you go to the headquarters in veilstone
To get to Snowpoint City you have to beat the Canalave City Gym Leader and then your rival will rush up to you and take you to the the top floor of the library. Professor Rowan will blab on about legendary Pokemon and stuff, and tell you to go to lake Valor. Beat the Team Galactic Grunt team members there then go to Lake Verity and beat Galactic Commander, Mars. Then Professor Rowan will ask you to up to Snowpoint City because he is worried about your rival. To get there you take Mt Coronet Path upwards from Celestic Town left route.
Go to valor lakefront and go inside the "forest" near the house with the girl who is looking for her key. Then beat the Galactic dudes and the commandor. :)
Go to the lake, which is nearby. Beat the guys. Then go to the team galactic HQ in veilstone. Take it from there