I have hundreds of small pen and watercolour sketches in upwards of 30-40 sketch books. Here are just a few from France. Any of these could be developed into full pictures if anybody wished.
I find that sketches are more fun revisiting than photographs and I use them as the basis for more formal pictures back in my studio. I make notes on the pad to remind me of the scene, where it was, the colours in it, etc.

Mandelieu 
Tourette-s-Loup 
Mandelieu Castle

Beaune 
Nyons 
Chaumont

Boules. Waiting Turn 
Fayence 
Souillac

Rocamadour 
Troyes 
Market at Troyes

Brantes