It says something when gamers are still fascinated by a game that came out in 1998, but that just tells you how good Pokémon Red & Blue were as games. Sure they’re incredibly dated by today’s standards, but in their prime they were a stunning example of what gaming could be.

But for all the obsession, even more than 20 years later, there are some secrets in this game that some fans may not be aware of. Sure we’ve all heard rumors about hidden Mews and the ability to catch anything in Bill’s garden, but there were some places hidden in the game some may have never found on their own.

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10 Game Freak Studio

Of all the entries on this list, this was probably the least hidden area in the game, but one that surprisingly many people weren’t aware of except through articles like this. In Celadon City players could come across a tall building called Celadon Mansion.

On the third floor of this mansion is a recreation of Game Freak studios with NPCs representing the developers. One of the developers promises to give you a reward for catching all 150 Pokémon, which turns out to be a signed diploma certifying you beat the game.

9 Victory Road Secret

There were a few players too excited to reach the Elite Four that they ended up blitzing past this important hidden area without realizing what they missed out on.

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Victory road contains puzzles that need to be completed for the player to progress to the final challenge. It’s while completing these puzzles that you find a room tucked away on the second floor. The only way to reach it is through a ladder on the third floor and it’s here that the player has the opportunity to catch the legendary firebird Moltres.

8 Seafoam Islands

Now we start getting into parts of the game the player would have had to go looking for in order to find. Seafoam Islands is a dungeon area east from Cinnabar in the middle of the ocean where players can catch many powerful water Pokémon and acquire many helpful items after solving various puzzles involving boulders.

For the players who were persistent in clearing out the dungeon they had the fortune of stumbling across the hidden legendary ice bird Articuno.

7 Abandoned Power Plant

This was a little trickier to find than Seafoam Islands as it required the player to have good memory or take a moment to examine the game’s map after acquiring the ability Surf. Just outside of the entrance to the Rock Tunnel is a channel of water then when explored leads to the Abandoned Power Plant.

Inside are several powerful electric Pokémon, but the true prize is the legendary electric bird Zapdos hidden at the end of the maze.

6 Museum Back Entrance

This hidden area of the museum was ingenious as many players learned of its existence in the beginning parts of the game when they couldn’t access it and likely forgot about it by the time they could.

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After obtaining the move Cut players could chop down the tree barring access to the back entrance and meet a scientist eager for assistance. This generous scientist gives players an Amber fossil that can be taken to a lab on Cinnabar Island to be turned into Aerodactyl.

5 Cerulean Cave

Sometimes referred to as the Unknown Dungeon, this hidden area may have been seen by eagle-eyed players after exiting Mt. Moon, but is inaccessible due to a water channel. Even after obtaining Surf and returning, players were blocked by a concerned individual telling of a powerful Pokémon inside.

It wasn’t until after defeating the Elite Four that players were granted access where they would find a cave full of rare and powerful Pokémon. Few moments in this game were as exciting as encountering that mysterious Pokémon at the end of the maze and finding out it was the legendary Mewtwo.

4 Legendary Truck

Perhaps the most known, but least encountered hidden area in the game is the infamous truck where rumor said that Mew was supposed to be hiding. The only way to find this area was either by accident or following some careful planning.

After obtaining cut from the captain of the S.S. Anne the player needed to escape the ship without going to the port, like fainting in a battle and waking up at the PokeCenter. The player then had to return with a Pokémon who knew Surf and just before stepping on the boat they could swim to the right and encounter a truck. No amount of pushing with Strength will move it and reveal the mythical Pokémon, but it does raise the question of why it’s there in the first place.

3 Glitch City

This bizarre area likely first discovered by speedrunners remained hidden from casual gamers for many years. To enter this nightmarish realm players needed to pay for a round in the Safari Zone, immediately leave, when asked if they want to leave say no, then save the game and restart it.

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After reopening the game the player needs to leave the Zone again and again deny wanting to leave, yet the player will find they can walk out anyway. After taking 500 steps the Safari Zone PA out of nowhere will come on saying the round is over and they’ll be transported to the lobby. Now when the player leaves they’ll step into a different dimension.

2 Ocean Safari

This is an incredibly useful hidden glitch area for players who want to catch all of the rare Pokémon found in Safari Zone without throwing rocks at them. To trigger it players need to initiate a round in the Safari Zone, immediately leave, this time confirming they do want to leave when asked, and once outside use fly to go to Cinnabar Island.

Sometimes players will see something amiss in the waters as the pixels can become distorted. If they start Surfing along the coastline they’ll be able to encounter Safari Zone Pokémon in the wild.

1 Oak’s Gym

Perhaps the most interesting hidden area in the entire game is Oak’s gym. It’s highly recommended you follow a guide, like this one on Fanfest, to find this hidden fight as it’s a convoluted process and easy to mess up.

After meeting the necessary criteria the glitch triggers a battle with Professor Oak who is easily the toughest boss in the game. Aside from the fact that this fight exists, it’s interesting that he also possesses one of the three starter Pokémon, as if he took whichever one you and your rival didn’t grab and prepared himself to be a final test for the player.

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