A good rail map is more than just a way-finding device, enabling users to navigate from A to B; it also orients the map reader in the city and landscape she's navigating through. A great map does both of these things and looks wonderful too — attractive enough to hang on your wall.
The London Underground (above) was the first subway system map to adopt a schematic design, and most of the cities of the world have followed suit. The tube map, originally designed by Harry Beck in 1933 (and not altered much since) is a true classic, which explains why its been featured as as graphic design on everything from tea trays, to bedsheets and even shoes.
The other 7 included here are all great maps in that they are both functional and aesthetically pleasing.
Washington, D.C.'s colorful spiral
Bright, colorful and graphic, the schematic D.C. Metro map indicates the Potomac and Anacostia Rivers, as well as public parks and county line demarcations, while still keeping things tidy and easy to navigate. It almost looks as if it's spiraling out from its center, perhaps an apt metaphor for the city it represents.
Sydney's flying angel
There's debate about which Australian city's subway is better — Melbourne or Sydney. Since Melbourne's map is in the midst of a redesign, and because Sydney's looks like some sort of winged creature flying off into the Pacific, Sydney gets the nod this time, for its balance between graphics and the coastal nature of this Southern Hemisphere powerhouse city.
Moscow's perfect circle
Since it was introduced in 1935, the Moscow metro map has been redesigned a number of times, and it has become more abstract with each iteration. It's notable for its center circle and the unique bubble indicators where multiple lines intersect.
Lisbon's graceful curves
One of the few non-schematic maps on this list (NYC is the other one), Lisbon's old subway map (it was just updated to a schematic version) is like an Impressionist painting in a field of Cubist designs. Just lovely, isn't it? As far as subway maps go, it actually shows more about the city that it runs through than the previous maps, with geographic details and major roadways, but is quietly minimalist at the same time.
Montreal's back in black
Montreal's black background is a bold design choice that would look great on a smartphone (though would be annoying to print out). It has been updated to a white-background version, but the elegant black-with-colors version is still a favorite of locals and visitors alike.
Madrid's mad blocks
Spain's capital city is a large and sprawling metropolis with a comprehensive and reliable subway system. Previous maps were useful enough, but none were notably attractive, until this brand-new schematic map was introduced just this year. It has won design raves.
New York City's iconic outlier
The New York City subway map is much beloved by New Yorkers and it helps riders navigate between the 469 stations (the greatest number of any system in the world). It is, uniquely, a geographical, not schematic map — though that type of map has been available since 1972 for those who prefer a more graphical interface.
The graphical map was used for 5 years in the 1970s, but New Yorkers voted on designs and overwhelmingly preferred the arguably old-fashioned design of a geographical map, which has been used ever since.
The advantage to NYC's map is that you get a good understanding of how Manhattan relates to the city's other boroughs, the East and Hudson rivers, and the city's parks. In a city where cycling, buses and any native New Yorker's fave — walking — is so popular, understanding where you are with specific detail is helpful for multimodal travel.