In a large bowl mix together the flour, salt, cinnamon, sugar. Add shortening. Using a pastry cutter or fork cut shortening into the flour mixture until it resembles peas sized shapes. Add ice water and mix until the dough forms a ball. Try not to over work the dough. Wrap in plastic wrap and chill for one hour. Cut and roll out to 1/8 inch thickness and place in a pie pan. Take a fork and poke marks all along the bottom and sides of the pie crust. This will help ensure that the pie crust will bake evenly. Chill the pie crust for ten minutes before adding your pie filling. This will help keep your pie crust from shrinking during baking.