Cherries, sweet or sour, are delicious pickled. They keep well - they can become wrinkled but the flavour is still good after a year. I like pickled cherries with pork rillettes, one of the easiest and most satisfying examples of French charcuterie.
850mL white wine vinegar
24 black peppercorns
6 bay leaves
1 clove garlic, unpeeled (optional)
1kg sweet or sour cherries, rinsed
Dissolve sugar in vinegar in a large non-reactive saucepan over a gentle heat. Add all other ingredients except cherries and simmer for 10 minutes. Allow syrup to cool.
Check cherries and discard any that are bruised or split. Trim stalks to 1cm and pack fruit into hot, sterilised preserving jars. Pour cold vinegar syrup over fruit and seal. Leave for a few weeks before eating.