The ferry from Snowpoint City takes you here. This is the Fight Area of Battle Zone. After you arrive, RivalBarry will ask that "what took you so long?" and threatens to fine you for 100 million! He then says that he wants to become the greatest Trainer ever, but a red-hair guy overheard and tells him to go to the volcano (which will be Stark Mountain) and hunt down the treasure. Barry bolts off to the Battle Tower. The red-hair guy introduces himself as Buck, then leaves.
You can get the ferry back if you need to. This is the location of Sinnoh's Battle Tower. If you're into competitive battling, like many of the residents of this town, this is the place for you!
You can get Scope Lens from a lady in the Poke Mart.
There are 2 Trainers blocking your way to Route 225, and another 2 block your way to Route 230. They will leave when you get your National PokeDex (which you should have done) and explored Battle Tower.
When you step into the gate to Battle Park, you will receive a Point Card. If you have any questions about how the Battle Tower works, speak to any of the women at the counter.
The Battle Tower, which is located here, is a great place to show off your skills. The first building you see here is the Exchange Service Corner, where you can exchange Battle Points (BP) you earn in the Battle Tower for TMs, held items, Vitamins, and even Rare Candies.
Since you don't have any BP yet, keep walking north to the Battle Tower.
The Battle Tower's interior.
This is where Trainers go to show off their skills. Here, the Pokédex is not added to, Pokémon don't earn Experience Points, and all Pokémon above Level 50 are reset to their Level 50 stats while in the tower. When you challenge the Battle Tower, you fight 7 battles in a row. If you win them all, you get BP. If you lose, your win streak (number of battles you've won in a row) is reset to zero. Basically, what you try to do here is not lose. Not all Pokémon are allowed— Game mascot legendary Pokémon and Event Pokémon can't be used. You also can't have duplicate Pokémon or held items. If you can win 100 times in a row (which is extremely impressive), you can get a star on your Trainer Card.
There are 3 attendants. Here's what you can do by talking to each of them:
If you talk to this person, you can participate in a Multi Battle, i.e. a tag team battle. You will be entering 2 Pokémon. If you want to participate in a Multi Battle with a friend by using DS wireless communications, say "yes" when the attendant asks if you want to form a tag team with a friend. If you say "no," you will be taken to a room called the Battle Salon where you can decide to team up with Cheryl, Mira, Riley, Marley, or Buck. (You haven't teamed up with Buck yet— we'll get to that part.)
Here, you can participate in Single or Double battles by yourself. For a Single Battle, you need 3 Pokémon. For a Double Battle, you need 4. Your 21st and 49th consecutive battles will be against Barry's father— Tower Tycoon Palmer.
Now that you have visited Battle Tower, the 4 Trainers blocking roads to Routes 225 and 230 are gone. You can explore any of these routes first, but the walkthrough will start from Rt. 225 and go clockwise.
Make sure that you heal your Pokémon before proceeding! You'll need to bring Pokémon with Cut, Surf and Rock Climb. Also, always let your leading Pokémon hold Amulet Coin or Luck Incense to gain double prize after Trainer battles, especially if you're running out of money.
This route is "a road of challenges", as a sign in Fight Area stated. There are tough Trainers and wild Pokémon in Route 225. Most Pokémon you'll fight are above Level 50.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
Head north to the small pool of water (after fighting the Trainers and cutting the trees to get the item), and Surf across it for a shortcut. Otherwise, walk west from the 3 Trainers and the item. You'll need to navigate the bridges and go up and down steps to get to the northern half of the Route, which can be a puzzle to get through the first time. Make a thorough search of the area, because a lot of valuable items are here. After using Rock Climb to fight the last Trainer on this route and grabbing the item, exit the Route at its northern terminus to end up in the Survival Area.