I imagine they sweated for a moment deciding if London Underground's labyrinths counted as individual pieces or the consolidated one they went for.

https://en.wikipedia.org/wiki/Labyrinth_(artwork)

https://labyrinthlocator.org/labyrinth/london-underground/?f...

Great site! I discovered just weeks ago and now use it every time I travel.

Labyrinths are really soothing for the mind in our overstimulated era.