Continue through the cave by turning and heading West, back up the stairs and through the passage.  You’ll immediately find another Hiker.

Battle: Hiker Jebediah (1024 Poke)
Opponent: Onix Lv 32

Check the outcropping South of the down-stairs area to find a Super Repel, then head back around the stairs to the North, ignoring the Strength boulder in favor of the item ball holding a yellow shard.  Scoot around and down the stairs and shove the boulder into its hole next, then proceed across it and back out of the cave.

Cross the water heading West, stopping off to the North in the grassy patch where you can find a ranger.

Battle: PKMN Ranger Richard (1680 Poke, pecha berry)
Opponent: Whirlipede Lv 28, Foongus Lv 28

Richard’s Whirlipede is a Poison Point variant, so be a bit cautious of that.  Thankfully, the pecha berry he gives you is a poison cure, so as long as you didn’t get more than one pokemon poisoned you should be just fine.

Head West through the grass to the house, where you can give your team a quick rest, and then head North either directly from it or via the overgrown path further West.  This will bring you up a small rise towards the entrance of Chargestone Cave.

Chargestone Cave is an interesting location unlike any other in a Pokemon game.  The entire cave is a dim blue-gray color, and in many places you’ll find floating, magnetized rocks.  You can shove these rocks through the air to get them out of your way, but you’ll need to be careful which way you push them or you can wind up cutting yourself off from where you want to go.  Additionally, the strange properties of the cave mean that you can level up a Nosepass or Magneton here to evolve them (where in the prior generations they will only evolve if leveled up at Mount Coronet).