The game's world is divided into two parts: the above-ground and the underground ones.
Each cell of the Alvilág duplicates each cell of the above-ground Kingdom and has the same coordinates with mark #
For instance, Kingdom 36-12 corresponds to Alvilág 36-12#.

When in the Kingdom, click the navigation button:
[{Image src='navi.jpeg.png'  align='center' }]

You will be instantly transported to the Alvilág:
[{Image src='podzem.png'  align='center' }]

The same button is used to return to the Kingdom.