That's actually really really cool, turning a claypit into a nature reserve. My brain now wants to change its vote to 'claypit' exclusively, but my inner botanist refuses to let it. Plus, as you say, weather. I can't imagine it'd be much fun in the rain.

I'm vaguely curious as to what the Black Country Museum entails, actually... there aren't that many corners of the country (Big Cities notwithstanding) that have enough stuff to require their own museum...