What is this Thomas Set?

I was not aware that they released sets with buildings for this range, but in western countries you could buy a washable playmat, Thomas, Percy, and James. Judging from the Thomas, this is an AquaDraw set, and if I remember correctly, as the engines puff along, they use water to "draw" railway tracks behind them.

Yes, I believe this is the Japanese version of the AquaDraw Thomas & Friends, for example here is another listing with a paint brush to guide Thomas:

This Japanese blog explains why this tunnel is awesome!

http://p-kiesfan.hatenablog.com/entry/2014/04/15/204131
http://page2.auctions.yahoo.co.jp/jp/auction/b207656460

I think it is a real range for the Thomas merchandise, there is a Thomas & Friends logo in a cloud in Japanese; HiT logo and copyright I believe in the bottom left corner of the box.