This one started with the crossing in the center.
For this one I used almost all of our tracks.
The starting point this time was a series of switches.
I tried a different starting point with this one: a series of switches branching off a central piece of track. The result was a very tight, squiggly set of tracks.
Once again, the starting point was a simple oval.
This one started with a plain rounded square and then started to branch out.