In a 3-quart saucepan, combine cider vinegar, sugar, candied ginger, salt, cloves, allspice berries, cinnamon stick, and lemon rind. Set over medium-high heat, bring to a boil, and cook for 15 minutes.
Add watermelon rind, return to a boil, and cook until rind looks slightly translucent, about 40 minutes.
Transfer pickled rind and spices to mason jars (of any size you prefer), packing to fill well, then pour brine on top to fully cover rind. Seal jars, let cool to room temperature, then refrigerate. Watermelon rind pickles can be kept refrigerated for up to 1 month.
