[2016.02/29 Update]
NOTICE: By testing in Minecraft 1.9-pre1 version, the tutorial content of Part 1 described below still work if you only do a small modification. If you are playing the new version, welcome to try this, too!
Please note that the subway map generators to be introduced in Part 2 no longer working in 1.9, and the equivalent solution is still not found yet. (as tested in 1.9-pre1) The subway generators to be introduced in Part 2 works Minecraft 1.9 Release version!


My Minecraft world Republic of FlashTeens contains 5 subway lines and 41 stations so far, most of which have the following featured mechanisms:

• Contains bi-directional platforms (except for terminal stations and FT Branch Line)
  
• Command block-driven minecart dispensers
  
• Station arrival announcement mechanism using the "/title" command
  
• Subway map generators throughout every stations
  
• [Jan. 27, 2016 Updated] Command block-driven automatic minecart stoppers (without any powered-off rails)
  

Curious about how to create a subway system with such mechanisms? Let's first take a look at how the station platform works!





This image assumes that minecarts come to the station from the right hand side. Before arriving the platform (usually 20+ blocks before the platform), the player in the minecart receives an announcement message title that indicates the minecart is approaching the station.

To generate the announcement title, first put a command block under a pressure rail, then input the following command in the block:
/title @p[c=1,r=2] title ["Arrival: XXXX Station"](This one is applicable for both 1.8.x and 1.9 version! For 1.9 version, don't forget to add the brackets [ ] outside the quotation marks " " , since the JSON format of /tellraw and /title commands become strict in the new version!)

or alternatively,
/title @p[c=1,r=2] title "Arrival: XXXX Station"(This one is applicable for 1.8.x versions only.)


In addition, you might either be surprised why minecarts can stop at the pressure rail, or reply "Why don't you directly use a turned-off powered rail?" Well, actually, in the past days, I used turned-off powered rail for stopping a minecart, but there was a problem. If you desire to pass through a station, such a design may be inconvenient since you would have to press an extra button that activates the powered rails.

However, in the new design (Jan. 27, 2016), the minecarts are actually stopped by a command block under the pressure rail, as the image above shows. The command that stops a minecart is:
/entitydata @e[type=MinecartRideable,c=1,r=2] {Motion:[0d,0d,0d]}where the data tag {Motion:[0d,0d,0d]} actually set the speed of the minecart to zero.
(Note: 0d is equivalent to 0.0, which is a double-precision floating point number that represents zero.)
The minecart stopper command above works in Minecraft 1.9 versions without any modifications.

Since the command is triggered only once whenever a minecart is detected, after arrival at the station, you may just simply press the 'W' key once to depart the station. Such a way is much more intuitive for you during the journey on subway lines!


Minecart dispensers. So far, they are already available in all subway stations since you must ride a minecart on the journey.
In my design, minecarts are always generated at least 2 block-high above the rails. In the example of the image above, the following command is added:
/summon MinecartRideable ~ ~-1 ~since the dispenser block is 3 blocks higher than the rail block.
The minecart dispenser command above works in Minecraft 1.9 versions without any modifications.


I will show even more about how the subway system work in a few days. You might be so excited to know how do I quickly update the context of the subway map manual book throughout ALL stations! Actually it isn't an enormous task for me anymore~~


Click here for Part Two!