Warm the vinegar and water together in a saucepan over medium heat. Add the honey, sea salt and pickling spice to the vinegar, and stir it until the honey and salt fully dissolve in the vinegar. Turn off the heat.
Drop the cucumber and fennel slices into a quart-sized glass jar, top with bay leaves and dill. Pour the seasoned vinegar over the cucumbers and fennel, seal the jar and refrigerate for a day before serving.