uNmINeD is a customizable two-dimensional Minecraft map rendering and browsing tool for Windows (⇒ download). uNmINeD is fast, easy to use, and uses simplified colors to make terrain and user-made structures more visible (⇒ examples). Scroll down and see the blog posts for screenshots, or visit the forum.
About Minecraft 1.13+ support
New releases for Minecraft 1.13+ are available at https://unmined.net.