Ooooh. Coral depths. Pretty nice sized area, took three maps to make it clear. Here you will find such equipment gems as Neptunes Trident, red satin sash, and others. Not to mention the fact that it is a great levelling area until your late 20's. Read carefully if you want everything explained to you. :)
Okay, here is where you should be starting from. Inside the South gate of DH. Just follow the map and try not to follow any strange paths if you can avoid it. :) Straight south from inside the south gate will get you to the Black Forest. Jeremiah the Bullfrog. Gotta love it. Fortunately he is kind enough to cast bless on you as you pass. If you see the frog, you're on the right path! Without a box of Alka-Seltzer, I can't be one hundred percent sure of that spelling.. :( Come to this man BEFORE heading into the ocean to get a tablet of effervescence. Eat it and get aqua-breath. This is the same man who has the dozen red roses also... Here ya go. This is where you actually enter the ocean. In this room type: PLUNGE, and you will find yourself on the path to both Mer-town and all the other fun things to be found in the ocean. Once you enter you will find yourself at the other #4. North is the way to go if you are interested in finding Davy Jones locker and all the neat things that are there, South is the path to Mer-town. Heading ALL the way down from here will land you at the #5 on the second map. Very close to Mer-town now, and you're also close to Maerdei as well... You're actually going to need detect hidden to see him, otherwise this room just looks like a dead-end. When you do come in and see him, go ahead and attack him. He will only take a single swipe at you before he transports you down into his locker. So here you are in Davy Jone's Locker. Not all that interesting really. That is, until you start searching for items. Yep, the red satin sash is in here, along with a few other goodies that I am sure you would like to get your grubby little fingers on. So, search away and have fun. When you are done, head south to #C. From C, just head up one (This will put you at the second C, then head west and nw until you are back in the tunnel that got you to Davy Jones in the first place. The ocean is an easy place to lose your way around in, so be careful.

So here you are at the bottom. Heading north will take you to the entrance to Mer-town, while heading south will take you to Maerdei. ALSO, it was just pointed out to me (again, thank you Nelkum) that going south is actually a shorter route really to get into Mer-town. Heading north from the bottom of the vortex here requires you to walk along either the south or north roads of town. So heading south from here to #7 will lead you directly to the Mer-Town square. :) From the room just north of #5, you have to OPEN ROCK, and then head east to get into Mertown. All of the little "g's" you see on the map are the locations of all the crab guards in CD. (Just in case you didn't know, the crab guards give you 90000 coins. 14 guards. Do the math. Just oabout 1.26 million gold :) ). Happy hunting... Well, the little arrow on the map means that it is a one-way exit from a room. So if you did happen to come this way, you can just head down here at #7 and it will put you at Mer-town square #15. Then just backtrack to here. Okay, so you really wanna get to Maerdei? Well, you're gonna have to make it through this maze to do it. From this room (#8) the path to get through to #10 is: s,e,s,n,e,e,n,s,w,s,n,s,n. Voila! Through the maze without a problem. Please be careful when doing this, though. If you lose track of where you are, you can't recall out of the maze. I say be careful because if you start fighting with something while in the maze, you might lose track of where you are. At the end, you will find yourself at #10. Congratulations! You made it through the maze! Maerdei is just around the corner. If you need to get back to the other side of the maze, and you dont wanna go through Maerdei, then just head south from #10 (marked #11 on the map). This will drop you back off one room east of #8. Remember, come south here to get back to one room east of #8. Hope you brought along a coupla friends. If you can't beat up Neptune, you probably can't beat up Maerdei. If you can, though, do it. She holds one of the only keys to get into Neptunes Throne (where the Trident is). Now, when she's dead, the key is on her corpse for the throne and the trident. Also check to see if she drops a key into the sand (requiring you to search for it). Well, you made it through Maerdei. From this room just past her, you will be able to recall back out of CD. Notice a little keyhole in the north wall? That is why I wasn't sure about the key. If she did drop a key when she died, it might unlock this door. Otherwise, you're gonna have to doorbash it to open it. I didnt even know this room existed until I sat down to map this place out. Had to have my warrior doorbash the darn thing. Once inside, though, you find some really interesting things. To the east is Jennie. Not happy, very fat. North will drop you at the recall point (Harakiem) in DH. Up will lead to the entrance of the High Tower of Sorcery(!), Down actually leads you to just inside the gates of Mahn-Tor, and West actually leads to the altar at the Temple of Dumathoin. (No, I don't know where that is).
So you actually made it down here? Good work. This is Mer-town square. All of the little T's on the map coming off the rooms are actually doors into little Mer-houses. Go have a good time. West of here is the village park and school, and east of here is the village shop. Up from this point will lead you to the corresponding #15 on the smaller map. This is the general area where the diving suit can be found. Head south from #15 and kill the guards. Make sure you get the keys from the corpse. Then open the door and head in. Kill all the guards and get all their keys. The west door from the central chamber is where you wanna go. The room north of #16 is empty save for a wardrobe against the south wall. DIG in this room until you uncover the key. Then you can unlock the wardrobe and head in. Inside is where you will find the... Yeah yeah. Maybe you got it and maybe you didn't. The suit pops at a reset IF and only IF NOBODY is in the area when it resets. This doesn't happen very often. The two rooms just north and south of the village shop will have a garden or something along those lines in them. When you are in these rooms, just type ENTER and you will find yourself beyond the garden and on your way to the Castle of Neptune.
So you managed to type ENTER in the right place, and here you are. Well, just follow the map and you will soon find yourself at the Castle (all the way to the right). Heading northwest or southwest from this room leads you back to the village. Oh yeah. Money money money. Total of six guards to be found here in this small barracks area. Gotta love rich mobs. This is the last guard outside of the castle itself. When you kill this one, be careful to watch for the key he will drop. After he is dead, you will have to SEARCH until you find the key. Once you have, welcome to the Castle of Neptune. Here he is. Finally. Kill him nice and dead. Might help to have one of your pals spell him down a bit. Faerie fire, weaken, and maybe blind would be good. When he dies, he SOMETIMES has the key to his throne. If he does, he will drop it. IF not, go back and pay a visit to Maerdei... Yeah, thought it was over and you had triumphed? Think again. Don't really see a trident in that chest, do you? Thats because its on a hidden/invis mob named T'Kull in the room. If you can see it, kill it (it's ALOT easier than Neptune himself to kill). When it dies, it will drop the trident. Once again, SEARCH until you find it. Then bring it to me to enchant! :)
Hope you enjoyed this little walking tour of Coral Depths. If you have any questions or feel that I left anything of importance out, just drop me a line. :)