Bring the water and peppercorns to a simmer in a medium sized sauce pan.
Then add the cranberries and simmer until the cranberries are totally cooked down and the liquid is bright red. This will take approximately 10 minutes. Remove from the heat and add in the apple cider vinegar and maple syrup. Stir and then strain the mixture through a sieve into a glass jar.
This cranberry shrub can be served over ice with equal parts club soda. Or as a cocktail by combining 1 ounce of gin or vodka with 1 tablespoon shrub over ice and topped with club soda.