Pokémon Crystal/Welcome to Violet City

Exploring Town
Just north of the gatehouse is a Pokémon center. Head in and heal up. Talk with some of the NPCs to learn more about the events of the previous game.

Trading for Rickey the Onix
In the bottom left of the city, there is a traditional looking house. A person inside offers to trade a Bellsprout for an Onix. Bellsprout can easily be caught on the prior route so it's a decent offer, especially if you want a rock type and didn't get one in the Dark Cave. Even though the game says to connect a game link cable, it's not needed. The Onix is named Rickey and is holding a bitter berry.

Earl's Pokémon Academy
Head north of the Pokémon Center to find Earl's Pokémon Academy. Read the notes on the notebook or on the blackboard to gain some tips about battle if desired.

At first, Earl is missing from the building. To find him, go to the gym exterior to find a spinning man in a green shirt with a strange way with words. He will ask "Battle GYM LEADER, win you did?". Say no and he will take you to the Pokémon School. If "Want to be a winner is you?" sounds good, then go inside to optionally ask him for more tips.

Sprout Tower
This swaying tower is home to a number of trainers, as well as some lore.

Pokémart
When you first arrive here, the Pokémart has the following items.

Other
In the house west of the Pokémart, you can get advice about naming Pokémon.

South of town is a berry tree with a przcureberry.

Further south is Route 32 which leads to the ruins of Alph and the next city.