Check out Matsuoka-san's Plarail swimming pool line to celebrate 10,000 tweets. He created tracks around the swimming pool.
Click here
He has some help from Shimamura-san, you can see the challenges they faced in the following video and another video.
They also tried running plarail underwater, as seen on the video.
NOTE: Matsuoka Jun is well-known for creating plarail stations based on actual stations and doing large scale setups. He also holds many plarail events throughout Japan along with Nayuho (who runs the Plarail Museum).
