This lovely photograph shows the castle wall from the other side. Were these just a lookout post or were they there to shoot the arrows through? Julie Riddiough thought they might be linked to a chapel: “Looks like a cross to me.” Susan advised: “It is a crossbow loop, for defending the castle.”
Image courtesy of Ray Brown, thanks to Julie Riddiough and Susan for the updates.
The ‘cross’ is similar to those on the lookout posts all along York walls.