Campaign Cartographer - Campaign Cartographer is the leading map making software for games (RPGs, miniatures and wargaming).
Tabletop RPG Map editor 2 - RPG Map II is a “tabletop RPG” oriented map maker, created with the “keep it clean & simple” philosophy in mind.
DUNGEONFOG - Online authoring tool to draw rpg maps & dungeons, create dynamic notes and share your maps online. Create dungeons, world maps and more with the easy to use map editor and create your game master notes dynamically.
Dungeon Scrawl - A dungeon scrawling tool by ProbableTrain
Wonderdraft - is an intuitive yet powerful fantasy map creation tool for 64-bit Windows 10, Linux, and MacOSX.
Roll20 - Roll20 is a suite of easy-to-use digital tools that expand pen-and-paper gameplay.