I currently have my RPG set up so that each town or dungeon is a Map class, which is composed of tiles and features. Tiles are the squares you walk on. Features are just that: features of the tile, such as trees, doors, walls, traps, etc. This may or may not be the best way to handle such things, and feel free to program your RPG differently, but that is how I have programmed my game and I believe it works quite well. If you haven't added color yet, this is probably a good time to do so. Also, it may be a good time to add tile manipulation, such as opening and closing doors. If you're not familiar with screen buffers, this is a good time to learn about them. They greatly increase display speed. One last note: This is also a good time to determine maximum map height and width you want, as well as a suitable scrolling method for larger maps.
Examples from GameTutorials.com:
Screen Buffer Tutorial
Console Tutorial
Color Tutorial