Where to catch Marill

In Paldea (Scarlet & Violet)

• East Province (Area Two) — Walk
• South Province (Area Five) — Walk
• South Province (Area Four) — Walk
• South Province (Area One) — Walk
• South Province (Area Two) — Walk
• West Province (Area One) — Walk

In Hoenn (Ruby, Sapphire & Emerald)

• Petalburg City — Surf
• Route 102 — Surf
• Route 104 — Walk
• Route 111 — Surf
• Route 112 — Walk
• Route 114 — Surf
• Route 117 — Surf, Walk
• Route 120 — Surf, Walk
• Safari Zone — Surf

In Johto & Kanto (Gold, Silver & Crystal)

• Mt. Mortar — Walk, Surf
• Route 42 — Walk

Marill — full Pokédex entry