Using a sharp knife, make incisions about 1 inch apart at least 1/2 inch deep all over the ham. Chop the rosemary and fennel; mash garlic to a paste. Add the rosemary and fennel seeds, 2 teaspoons of salt and combine. Stir in the olive oil and 1/2 teaspoon of pepper.
Using a wooden skewer, push about 1/2 teaspoon of the garlic paste deep into each incision of the ham. Rub the remaining paste all over the ham. With the ham fat side up, use a knife to score a 1/2 inch deep criss-cross pattern. Put the ham in plastic wrap and refrigerate overnight.
Take ham out of refrigerator and let set to room temperature. Preheat the oven to 300°. Place the ham in a roasting pan and rub the ham with generous amounts of salt and pepper. Roast in the oven for 3 hours. Remove the pan from the oven and put juices in a small sauce pan. Return the ham to the oven and roast for 3 hours longer or until it is deeply browned.
Spoon any remaining pan juices and fat into the small saucepan with the other pan juices. Skim off the fat. Let the roast stand for 15 minutes before carving. Heat the juices and put in a gravy boat. Serve on a bed of fresh arugula.