Why did I think that......

.....the Mono Monday challenge was something to do with 'Mysterious'?  Is that coming up or has it been before or is it another challenge altogether?  I'm confused.......  Think this is some sort of blackthorn and I liked the contrast with the roughness of the wall.  Was going to do these gravestones....the mystery being who they might have been.  Another sunny day - what a bonus.