Back before the Nintendo Switch, before Niantic's massive success with Pokémon Go, there were the GameBoy games — from classic, to color, to advance, and so on. On the GameBoy Advance, Pokémon Gold & Silver were released, the second generation of Pokémon finally introduced to us.

These games, despite being among the best Pokémon games, were not without their faults and left some glitches littered around Johto for us to find, meaning many secret locations. And, of course, some hidden areas were put in there deliberately for players to find if they explored hard enough.

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Between the glitches and the deliberate tricks, there certainly was a lot in there. If you never found all of the hidden areas (and it's unlikely you did...), we have you covered. Let's take a trip into the past and explore — get fishing out that old GameBoy.

10 The Ruins Of Alph

Let's start with the obvious first.

It's not so much a hidden area as an area with a bunch of hidden parts. You'll find this early on in the game, but you'll only be able to access the first puzzle. They key about this one is not to forget about it and to keep coming back because if you do, you'll find more and more puzzles. The more you solve, the more hallways you'll be able to access — and those hallways hold different varieties of Unown.

There are twenty-six total, one for each letter of the alphabet. Return to the ruins throughout the game to ensure you find them all, because you won't find them anywhere else.

9 Kanto

There's a pretty huge surprise area in these games – Kanto.

Supposedly, once you beat the league, the game is complete (aside from completing the Pokédex itself). But that's actually not true! You can then go visit Professor Oak and get a ticket to Kanto, which opens up a whole new region, set of gyms, and league. And this brings new Pokémon to the game too that you may not have been able to catch otherwise.

8 Cerulean Gym Fishing

Catching Pokémon within a gym? Impossible!

Or not.

It's one of few indoor places you can do this, but the water in Cerulean City gym is actually fishable, so you can cast in a rod and get those water Pokémon. Of course, it's a while before you can get here — you have to beat the entire Johto league before you can travel to Kanto, as we just said — but once you've unlocked the whole game, there are secret fishing spots within the gym.

Worth doing just to say you have a Pokémon you caught in a gym!

7 The Safari Zone

We hear ya. The Safari Zone isn't present in Silver, Gold, and Crystal — they claim it's closed once you find it in Kanto. But if you use a cheating device, you actually can access the Safari Zone.

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Yes, it's cheating. But if you really want to open up the entire game and have a cheating device... have at it. We don't advocate cheating (...really), but those devices are so common that many gamers have one lying around and hey, if you're going to use it, you might as well know its full potential.

6 The Glitches

Speaking of cheating, there are many glitches in the game that can be exploited using a cheating device. These will allow you to walk through walls, trees, buildings, any places that the trainer shouldn't really be able to walk. It kind of ruins the fun of the game if you do this from the start, but if you've really exhausted everything there is to do in Gold & Silver and want to run around doing something new within the world... Have at this.

5 The Whirl Islands

The Whirl Islands themselves aren't hidden so much as many areas within them are, much like the Ruins of Alph. We would highly recommend looking up the extended details about the Whirl Islands so you can fully explore each one and get all of the items that are littered around here.

But the best thing about the Whirl Islands is that Lugia is lurking within them. Level forty for those who play Silver, level seventy for those who play Gold, he's worth it either way. What legendaries aren't?

4 Berserk Gene

Not many people find the Berserk Gene in these games. It's another Kanto secret, so it's one to save for once you've beaten the Johto league and are exploring the new (or rather, old) region. It's exclusively found in these games and only this spot, so it's definitely worth getting. It's an item that both raises Attack and confuses the opponent in battle.

Remember Mewtwo's cave from the original games, by Cerulean City? Head that way and talk to the man with an Itemfinder — he'll point you to it. Sure, it's not the most valuable item in the games, but it's a neat one to have for the exclusivity.

3 Union Cave

Union Cave itself is not difficult to find, but the Lapras inside of it is.

Once you've beaten Morty, you have to visit the cave on a Friday afternoon to find Lapras. This is a great water Pokémon to have, so it's well worth making the trip just for the Pokémon.

Union Cave itself isn't hidden, it's just a little difficult to get to.

2 The Hidden House In Olivine City

This was intended to be a thing before the game's release, but changed — but it's another area that can be accessed with your cheat device.

Inside the house is a Rhydon that turns into a Clefairy after the woman remarks on it being sick. This is more of just a cool, gimmicky area than anything else — there isn't much to be gained from coming here except to see it.

1 Bill's Garden... Sorry, Though...

When players were roaming around the Pokémon world and the generation two games were newly released, there were tales (for those of us who are old enough to remember) of a secret garden by Bill's house with all sorts of rare Pokémon. Sadly, players searched and searched, but this never appeared. Presumably this was a rumor started by players or something that had been in the works but never actually came through in the games.

Boo!

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