[INJ] Metal skatepark...hmmm I've not come across one. All the ones I know are concrete, with the odd wooden ramp thrown in for old-times' sake (plus some trees and fencing). I've now done some further searching and found that you are right. I was working mainly from a quote from a skateboarding magazine that concrete is the industry standard these days. My apologies if that threw people completely off the scent.

Ooh, is it me? OK, I am thinking of a ABSTRACT, with animal, vegetable and mineral connections.