Shangri-La is one of infinite timespaces portrayed on Noein: To Your Other Self. Originally, Shangri-La is a fictional place on various stories where you can find true peace.
Noein wants to merge all timespaces and fuse it to Shangri-La to create a single timespace where who he says "No more pain and suffering". But doing this will make the universe collapse and all timespaces disappear.
It is a wide field covered with grass and some mountains.