But I finally found a worthy adversary for The Cardvaark. Who could this upstart be? Why, it's a mole decked out as a digger for the Warsaw Metro. The first (north-south) line of Warsaw's Metro system has been operational since 1995. A second, intersecting east-west line is still under construction, thus our shovel-ready friend. (But that's not the 'hole' story, as we'll see.)
In case you've forgotten about Cardvaark, here's a reminder below. And much more here. Much as it pains me to admit, I think you've got to give hand it to the Poles on this one.