Here is a close up of the island which has made the inner loop possible. Originally, we thought we could simply add the new loop to the periphery of the old layout. But we quickly realized that doing so would make it difficult, if not impossible, to reach critical sections of the layout; especially those closest to the wall.

 

Once all this is completed, we will be able to reach the goal of running two full trains at the same time (and, possibly, doing some vacuuming at the same time)!

The Island