Whisk together the water, vinegar, sugar and spices. Bring to a boil, then reduce and simmer for 5 minutes. Let solution cool completely to room temperature.
Peel cucumbers. Slice longways, scrape out seeds with a spoon like hollowing out a pumpkin, then slice cross ways into 1/2 inch slices.
Slice onions into strips 1/2 inch wide by 1 inch long.
Place everything in a glass dish, or jar, and pour cooled solution over cucumbers and onions. Refrigerate 24 hours or longer.