Rinse elderberries and pick out dirt, stems or dried out berries.
Place berries in large bowl and mash them.
Pour vinegar over and allow to stand 24 - 36 hours, covered with a clean tea towel or cheesecloth.
Strain through cheesecloth. Allow to drain slowly for up to 24 hours (if you press on the fruit while it is draining the vinegar will be cloudy).
Pour juice into a non-reactive stockpot or preserving pan (a stainless steel saucepan will do). Stir in the sugar, bring to a boil, adjust heat, simmer for about 15 minutes. Watch carefully as juice reaches the boiling point - it can boil over very quickly!
Let cool slightly, pour into clean bottles with corks, label and store in a dark, cool place.