Cinnabar Island

Cinnabar Island is a volcanic island situated south of Pallet Town and west of the Seafoam Islands. It was well known for being a base of scientific advancement, with fields such as cloning and reanimation making huge steps.

Pokémon Mansion
The Pokémon Mansion is a former research center which was abandoned, which appeared to focus primarily on cloning Mew. It is now home to wild Pokémon and looters. The door key for Cinnabar Gym is located in the mansion. It is also the location of Burglar Simon.

It was destroyed when the volcano erupted.

Pokémon Lab
The Pokémon Lab is the current research center. It appears to be focus on reanimation as the researchers there are capable of restoring the various fossils back to life. It also appears to have some connection to trading as there are three people willing to trade.

It was destroyed when the volcano erupted.

Cinnabar Gym
Cinnabar Gym is run by Blaine. It is set up in a maze-like structure with gates being guarded by questionnaires and trainers. Continuing with the themes of knowledge and theft, the gym is populated by intelligent and cunning trainers.

It was destroyed when the volcano erupted and its services as a gym were moved to the Seafoam Islands.

Volcano
The entire island is situated on an active volcano which was previously thought dormant. When it erupted, everything bar the Pokécenter was destroyed.

Blue came here to meditate when he got stressed.

Blaine
Blaine, described as the "hot-headed quiz master", is an intelligent scientist who also doubles as the local gym leader. He primarily favors Fire-type Pokémon, but in FireRed, he swapped to Rock-type Pokémon and was given the name Dwayne by the Hivemind. He used Psychic-type Pokémon in HeartGold and gained the nicknames Psyain and Gain.

Burglar Simon
Burglar Simon was a thief at the Pokémon Mansion who became infamous when he trapped Red and Abe in a corner for several hours, forcing them to black out