Dragon's Den — Pokémon SoothingSilver
Every wild Pokémon here, by encounter method.
Dragon's Den lists 6 Pokémon across 7 encounter methods (surf, old rod, good rod, super rod, and more), between level 10 and 40. 2 of them are on no other route's wild tables in this guide: Dratini, Dragonair.
Dragon's Den in other guides
The same area in other ROM hacks on this site. Each one has its own encounter table.
Opens up at 7 badges — Glacier (Pryce, Mahogany).