I always wanted to have some sort of fishing-only map, where players can fish for quest fish and other stuff in completely safe environments.
I am not sure if a map like this already exists, but I nevertheless took my own swing at it. And why not share the results?
This map is heavily TEdited. I've cleared the whole world, and create a bunch of little shielded islands where people can fish in peace, all reachable through teleporters.
The map was created in no time at all. Don't expect grand works of art, there's nothing museum-worthy here.
Also, don't expect to find any phat lewd on this map. I think Terraria is most fun when you earn your own keep, get your own gear, and be happy with your accomplishments.
Nevertheless, I left a decent fishing pole and 50 worms behind, so that even new characters can make a start. (Look inside the left-most chest at the start.)
In my experience, the angler will give more than enough bait as rewards for his quests, so you should be able to keep it going. If not, then you're off to find more bait on other worlds.
Feel free to give me any criticism and/or point out flaws. Every fish/item should be catch-able, all the biomes should be present, but my gawd, I am not perfect. No sirree. Mistakes/oversights might have been made.
Edit #1: To my dismay, some environments don't seem to work in multiplayer. I have no idea why this is the case and can't fix it. Very strange.
Edit #2: Apparently these environments were too deep, even though they were surface level, and worked in single player. Map is fixed now.