Names are always tough. It would be easy to give it a sensible name such as "Fishbay" or "Seasedge" but I don't think that's what your looking for. I am also not very creative with names and in my kingdom of Shendenflar campaign setting most things are named for what they are or what they do or where they are. (IE Riverhewn my capital city that was named for the fact that over the millennia two rivers carved out the island that it sits on) Fantasy names run the gamut between functional and accurate to almost unpronounceable. (such as any Elvish city) The bottom line is a name is not just a name, it is a history and a backstory and a future potentenial. You might try just writing down a bunch of names that describe the area for what it is or does or was or might be. Then write down a bunch of "fantasy" sounding names (things with apostrophe's in odd places are a good place to start) Ancient languages are another good resource to tap for interesting sounding names. I am not a fan of "random name" generators for something as well defined as a large capital city but there are some very good ones out there and they may provide a spark of inspiration. The name will become history and perhaps even legend someday so it's worth a little work to come up with something you like. Take your time and look at the names you've written down. I'd be willing to bet that one of them will keep clamoring for your attention. I wish you good luck