From Bulbapedia, the community-driven Pokémon encyclopedia.
Hearthome City (Japanese: ヨスガシティ Yosuga City) is a city in the region of Sinnoh. Hearthome City is home to the Super Contest Hall, where one can take place in the Super Contest, a Gym, the Pokémon Fan Club, and the Poffin House, among other things. An old man will give the player a Happiny egg here. Hearthome City started as a place where people and Pokémon gathered and grew into a center of commerce, and is consistently voted as the most desirable place to live in all of Sinnoh. It is also a gateway to nearby Solaceon City and Pastoria City.
Hearthome City is a child-friendly city, and there are many families and young mothers living there. Most of the buildings use elevators instead of stairs so that small children and Pokémon can move through the houses. There are prams strewn through the city. The citizens scrupulously keep their city clean.
There is plenty to do in Hearthome City. There is a church there where different cultures meet. There's also a nice fountain and Sinnoh's branch of the Pokémon Fan Club.
The biggest attraction, garnering contestants from all throughout the region, is the Super Contest Hall. The city's Gym Leader, Fantina, is a self-proclaimed master at Pokémon Super Contests.
A notable attraction is Amity Square, where trainers relax with their Pokémon. Eleven different types of cute Pokémon will follow the player about in Amity Square, and many Pokémon wander about the city outside of their Poké Balls.
Inside the Pokémon Fan Club (numbered 3) player will receive the Poffin Case, needed to bake Poffin. The Poffin House is also here, where coordinators can bake Poffin to boost their Pokémon's condition for Pokémon Super Contests, either alone or through DS Wireless Communications with people nearby. Up to four people may bake at a time.
As the player enters Hearthome from the western side, there is a house with a sign. This is where the Berry Master lives; each day he will give the player a new Berry.
Also of note are Bebe, the system administrator for Sinnoh's Pokémon storage system, and Mr. Goods, a bemused man dedicated to rarities who gives out goods to decorate the Secret Base in the Sinnoh Underground with upon completion of certain tasks, such as using the GTS or defeating all eight Gyms.
The population of Hearthome City is 55 people.