CITY MAPPING

Start with laying out main roads. Ideally you want them about 2-3 wide. There should be at least two in a + or four in a # pattern. You'll then want to add smaller roads. Only after that should you start adding buildings.
- The main roads should provide easy to follow lines from the main point in town - gates to castle, in this case.
- A fountain is usually in a highly-viewed area. Near the gates of the city or in the center. Definitely on or near the main thoroughfare.
- Inn/Pub/Weapon/Etc should be near to each other in the same district. You can move a pub a bit away (or have a secondary one in a larger city) but you want to keep them in relatively the same area so that the player doesn't have to go too far to find what they need.
- Castle entrance should be either behind the town (thus making the city a focal point if attacked - so the enemy has to fight their way through the streets before reaching the castle) or in the middle of the city (for the same reason.) The first, if the city has defensible walls/terrain behind it (I tend to go for mountain/lake myself).
- Not every house needs to be opened to the public. And easy way to fob this is to block the doors of houses with other houses~ (Check the images below for examples.)
- The usual city in RPGs have different areas - the shopping district, the poor district, the noble district, the castle and gardens, the scholar/museum/public works district and the residential district. Keep in mind that you can allude to these without actually having to create them.

Here are some examples:-


Also, this thread might help you out!