Just how this city appears depends on the version of the game you are playing.

Black Version:
You will find a packed modern city. While still spacious it is meant give a progressive feel. The entire city, unlike White Version, is level.

White Version:
You will find a more pastoral city. It meant to show a place that treasures it heritage. There are a number of short stair cases as you navigate the city.

Regardless of the version, you will find Ghetsis giving a speech near the entrance of town by a Fountain. He speaks of N's deeds, teaming up with the Legendary Dragon to create a world for Pokemon alone. This bothers a lot of people in the area. He is quite a good public speaker if the crowd is to be believed. Once they clear out, you will find one person you know, Alder. He will then introduce you to the other remaining people, Iris and Drayden. Afte the speech, Drayden, Iris and Alder will talk about things, getting updated on the story of N and the legendary Dragon Pokemon. Iris and Drayden will ask you to visit them at Drayden's house. There are few places of interest to visit in this town first.

Head upwards from where you head the speech. You will find the Gym, but you cannot go in just yet, instead visit the house to the right of it. The old man inside will give you a number of props if you visit him four days running. Head over to the right and down You will find a house that you can enter above the Pokemon Center. Inside you can trade a Pokemon from the opposite game that knows the move "Charge". Any number of Pokemon will know this move, but Blitzles are probably the easiest to catch and trade around for this. You will receive the hold item Cell Battery. This one-time use item will bolster the Pokemon holding it when hit with particular attacks. Time to hit up the Pokemon Center then head up the street to the left of the Center. This leads you to Drayden's House.

Once inside, Drayden will explain what he knows about Zekrom and Reshiram. He tells of two heroes who split an all-powerful Pokemon into two parts. Those parts are Reshiram and Zekrom. While he can tell this story well, he does not know how to awaken the Pokemon slumbering inside the stone. At this point, either Drayden (for Black Version) or Iris (for White Version) will announce they are the Gym Leader for the city and head into the building for you challenge them. This is going ot be a hard fight as many trainers will have Dragon-type Pokemon which have very few weaknesses. This is the final Gym, so be ready for a fair number of challenging fights ahead.