Impassable Din Daeng (BKK intersections 3)

It has been a while since I've done one of these.  For your topological and civil engineering pleasure, I present  Din Daeng intersection (แยกดินแดง):

Notice how the expressway obscures key details?

Magnified view. We now see a tunnel, but where does it emerge?

This intersection has a special place in my heart. Last month, J1 and J2 played in a squash tournament at the Thai-Japan Youth Centre. It isn't visible on either map I've included, but is just to the northeast of the intersection.  Since we live on the west of the intersection, we needed to cross somehow.

After three failed attempts (following the driving directions on google maps) to get through from west to east, I ended up parking our car in one of the small side streets and we just walked. The walk took about 30 minutes...

Ratchaphruek and Nakhon-In (BKK intersections part 2)

On a recent errand, I was reminded of another wonderful Bangkok "intersection" between Ratchaphruek and Nakhon-In. I use the word "intersection" loosely, since these two roads don't actually touch directly.

This actually is a cool intersection to drive through, assuming that you are only planning to go straight through, especially driving straight on Ratchaphruek through the <hint>underpass</hint>.

Here is a link to the location on Google Maps: intersection2. If you want to answer my questions about the intersection (what does the graph look like, how many transitions are possible, etc), you probably need to go to the interactive map. Frankly, I'm not even sure I included all of the relevant pieces in the picture above. This is one of the charming features of intersections here: sometimes, you have to prepare well in advance of clear signage and may find that you've gotten stuck and can't cleanly make the desired transition.

How many ways through the intersection?

Here is a "typical" intersection between main commuting roads in Bangkok:

Googlemaps link for this location: Ratchapruek and Boromarachachonani

I use quotes because it has a typical level of complexity, but almost every intersection is structured differently. Apparently, the civil engineers here wanted each interchange to be its own special little snowflake. One implication is that, for the drivers, it is very difficult to correctly navigate through the first time you encounter a new interchange. Also, if you are used to one transition through the interchange, you may be completely lost coming from a different direction or leaving a different direction.

Your mathematical challenge, should you accept it:
Count how many ways there are to go through this interchange

It might help to draw a diagram that abstracts the roads a bit, but makes it more clear. At least it will make it more clear to me what you've gotten wrong when I go to correct your work!