After a long journey through snowy routes, you finally reach Snowpoint City.
Explore the City
East of the gym, there is a hidden Hyper Potion.
In the northwest house, if you have a Medicham, you can trade it away to get a Haunter. The Haunter is holding an Everstone, so it won't evolve when you receive it. However, you can use the Everstone to prevent your own pokémon from evolving.
Enter the Snowpoint Gym when you are ready.