That's a bit of bad luck, Dave, but at least your all right. It happened to me the first time I went out on a mountain bike, about ten years ago, brand spanking new Cannondale Jekyll 2000. Tried to get up a tough hill, snapped the chain, broke the rear hanger tore a hole in my Race Face trouser, falling off and rolling down the hill backwards in a most indecorous manner. Meanwhile my mate was rolling on the floor laughing he head off. I was most vexed.
I live very near Brackley, often ride through or near there, may be I'll see on the road.