How To Get To Blackthorn City In Soul Silver?

First you have to catch the red gyarados in lake of rage while your by the lake of rage go to the person with the dragonite (lance) he will ask you to help him. Click yes then go to the house in mahogany town that is next to a weird tree. Lance will be in there he will move a box that was covering some stairs then follow him and defeat everyone down there.
Then go to goldenrod city go into the place where you can have your picture taken (when you go to the right place a team rocket member will give you a team rocket suit. Then you have to go to the goldenrod radio tower and you will be allowed in. Then heart s and you have to go up through the radio tower when you complete this part the person who stopped you from going to blackthorn and asked if you wanted a rage candy bar will let you pass.

Visit lake of rage if you havent.. Catch red gyrados talk top lance,.go to mohagany town and meet lance in one of the buildings..defeat team rocket..head to golden rod and go into the underground picture shop.. A team rocket guy will give you a uniform now go to the radio tower and do your thing..then back to mohagany..he should let you through.

If you don't want 2 go throw all the dramatics first defeat team rocket in Mahogany town (that step is in-escapable) then buy a Ragecandybar from the guy to the right of the city. Afterwards go to Goldenrod city and start the little mini-quest where you must defeat team rocket AGAIN *sigh* at the radio tower. After prof. Elm calls you asking you 2 find out wats going on, go 2 the tunnels under Goldenrod until you find the old dress-up room. There will b a guy there dressed up as team rocket and he will give you a uniform 2. Once you get the uniform DO NOT ENTER THE RADIO TOWER! Trying to go up the stairs will cause the guy with the red hair who says you r weak will come and make you take off the uniform, never to put it on again. Instead head back to Mahogany town and now try to go past the guy at the route that leads 2 Blackthorn. Poof! You just made it in2 Blackthorn city!!! (sadly I didnt figure this out soon enough and went in2 the tower and got striped :o

You need to either catch or destroy the Red Gyarados.After that, go talk to Lance.He'll
ask you to help him.Say "yes".Go to the souvenir shop and wait till all the talkings done.
Go down the stairs after Lance.Defeat Team Rocket.After that go to the place where
you can take a picture of yourself in a Team Rocket suit in Goldenrod City.Then go to the Radio Tower.Go upstairs to the office.Talk with the person in the office.Then go to the Goldenrod City underground storage room.Go save someone in the center of the storage room.Then you can go to the freakin' Blackthorn City.There you receive the
Tidal Bell you also need to find Lugia with the Silver Wing.You DON'T need Lugia to go to Blackthorn City.You're able to catch Lugia only when you get the Tidal Bell from
Blackthorn City.Then you go to Whirl Islands to catch Lugia or Destroy Lugia then come back to catch Lugia after you defeat the Elite Four.  
  Thank You!

There are 3 steps to get to blackhorn city first you must destroy the teem rocket transmitter in mahogany town. Second you must beat teem rocket at the radio tower in goldenrod city. Third you must go back to mahogany town and through route 44.

Is there a guy in the way ? Then you must go to olivine city an then to cianwood to get a cure fore the ampharos in the light tower and then you can go past that guy an you must go tro a ice pokemon cave I recomand to catch and train one before you challenge the gym leader there and sorry for my mistakes with some words

Go to radio hub and beat team rocket

This guy would not let me in

You don't have to catch red Gyarados

There are 3 steps to get to black thorn city

I still can't get it theres no team rocket guy and I already beat team rocket and still nothing.

Go to team rockets hideout beat every1 then go to the radio tower beat team rocket he will let you past

Defeat
team rocket  then go back to the dude that didn't
let you go  though

I beat team rocket and they're gone from the radio tower, but the guy still won't let me through! Please help!

I tried going from the ice path but I got stuck on the 2nd part of ice it was so hard to get  to the other side but I couldnt. Does the ice path cave lead you to blackthorn?

If you defeated the boss of team rocket go to the underground path and find the boss of the radio tower :o

I can get to the Ice path but I can't get though help me please

You can't use fly if you havent been to blackthorn city

Actually team rocket does let you pass you  have to pay $1000

Ok I caught the red thingy defeated team rocket in their hq killed gym boss and the rocket team havent invadied the invadied tower help me invadied send it to my youtube account invadied

Fat fat fat

Fly

You need to catch lugia