Arrows v artillary

[Didz]

According to wikipedia(albeit i admit, the article doesnt state a source for this information) Corfe Castle fell due to an inside betrayal after being besieged for only 2 months http://en.wikipedia.org/wiki/Corfe_Castle

I was relying on this site for the information:
http://www.thedorsetpage.com/locations/place/C350.htm

On mayday 1643 a troop of republican horsemen entered Corfe to find the Castle barred. Corfe was held under siege for three years, finally falling on 27 February 1646.

I suspect it comes down to 'when is a seige not a seige', if the garrison are unable to leave the castle due to the presence of enemy troops are they still under seige even though the enemy are not actually attacking the castle.

The man who bretrayed Lady Bankes was one of her officers, Colonel Pitman, he led a party of Roundheads into the castle via a sally gate. The Roundheads had reversed their jackets and were mistaken as Royalists until it was too late.