Town Map is an item in the “Gameplay” category (Key Items).
In-game descriptions
| Emerald | Can be viewed anytime. Shows your present location. |
|---|---|
| FireRed / LeafGreen · Diamond / Pearl · Platinum · HeartGold / SoulSilver · Black / White · Black 2 / White 2 | A very convenient map that can be viewed anytime. It even shows your present location. |
| X / Y · Sun / Moon · Ultra Sun / Ultra Moon · Let’s Go, Pikachu! / Let’s Go, Eevee! · Sword / Shield | A very convenient map that can be viewed anytime. It even shows you your present location in the region. |
Where to find it
Not placed on the atlas maps (so far: Red/Blue and Generation 3).
Sources : PokeAPI (items, item_flavor_text, machines) · atlas · pokeemerald species_info.h