Sandal Castle, Henry VI, part 3 : 1, 2
The castle's remains (although not much is remaining) are still there at Sandal, Wakefield:
Latitude: 53:39:31N Longitude: 1:29:25W
The field of battle in scenes 3 and 4 refers to the Battle of Wakefield, which took place on Wakefield Green to the west of Sandal Castle.
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"It is good to have an end to journey towards, but it is the journey that matters in the end"