Put the gammon a deep saucepan. Add the cider, then enough water to cover the meat fully. Bring to the boil, skimming off and discarding any impurities.
Add all the other ingredients and bring to the boil again. Cover and gently simmer for 1-2 hours depending on what you want to do with the ham.
If you want to roast it, take off the heat after an hour and let it cool for an hour in the liquid. Then take it out of the stock, score the fat into diamonds and stud with cloves. Glaze with marmalade or honey mixed with mustard or, maple syrup with spices etc. Roast for 20-30 minutes in a preheated oven (at 190C) for 20-30 minutes until golden and crispy.
If you want to use the ham for salads, soups and stews, cook the gammon for 2 hours, then take it out of the cooking water and cool a bit. Remove the fat and shred the meat into chunks. Store the chunk in the fridge.