I remember when I was following the Grateful Dead, my feet were always dirty, but when The Dead played in door arenas, my feet were at their blackest. Supermarkets and straggly the racetrack are other places my feet get extremely dirty. Of course I’ve been going barefoot now for awhile and my feet are stained dirty on the bottoms anyway.
I find my feet get really black in the drying area of a car wash, especially if it hasn't rained in a while. another place are multi-story covered car parks
Hot city streets, parking garages, gas stations, the subway, auto racing venues, big old discount stores. Lots of fun to be had at all of them. The state fair is also a fun place. Downtown festivals and concerts are hard to beat.
maybe i'ma weirdo but my feet never seem to get black unless i'm in the garage. probably because i wuss out before entering a store and put on my flipflops. even now that i'm going to college.. they don't get black. not even after dance class.. weird
i'm with boogabaah. it's hard to get my feet to turn black, probably because my soles are tough so the dirt can't stick very well.
maybe thats it.. or the fact that most places have carpet .. or i'm outside. it i was on an unswept tile like floor.. maybe
When I was in college, I used to go to class barefoot all the time. It was amazing how black my feet got. But going barefoot to concerts, no matter hard your feet are on the bottoms, your feet will get black.
Concerts, parking lots, stores, city streets, subways are all great places to get dirty feet. I loved Dead shows! The Meadowlands, Madison Square Garden, Philly, got totally black feet! Coney Island in Brooklyn, NY, too.
I don't usually care for getting my feet dirty on purpose, although neither do I avoid it. However the blackest they've ever been was at the bus station in The Hague, I'd just missed the bus and it was Sunday so I had to wait almost an hour. There was oil everywhere and my soles were pitch black. However, when I got off the bus I had to walk about one block and by the time I got at my destination I looked for it was a place I didn't want to track dirt in... in just that short distance and even with all the oil and gasoline and other polluted crap, it was almost all gone... my soles were only a light dusty grey. I've never gotten the green to stick to my feet either; sometimes other barefooters report that after mowing the lawn their feet are green and it sticks for a long time... Just out of curiousity I usually check after mowing, but they're just slightly greenish and it's always gone by the time I've walked up and down a few times putting away the mower and stuff. Maybe the mower I use -one of those mechanical push mowers- doesn't tear the cut grass up as much as the far more powerful modern mowers do, so there's less grass juice?