Test maps

I’m looking for maps with just one element of some type for debugging purposes.

E.g.,
-map with just few fences; one straight, one curved, one bent with angle.
-map with railroad. One set of straight track, curved track, and one set of two tracks merging together
-map with grounded and elevated highways.
etc.

For simple ones I can probably make with JOSM. But with so many types of tags, I hope there are existing such maps.

Thanks

On http://wiki.openstreetmap.org/wiki/Develop you have a link to http://apis.dev.openstreetmap.org/ where you can upload OSM data for testing purposes without touching the real OSM data.

Or do you mean only the display (rendering) of certain Map data? Then you will have to setup your own mapnik or osmarender rendererer, tirex or maperitive to name but a few.