@Isaiah I had the same thought. Looking historically, a well fortified location, during medieval times,can repel a large force with a fraction of the man power. A mere 100 could defend against a force vastly larger than them. A defending force of 1k would easily repel any assault by a 4k force. Laying siege is definitely out of the question due to sieges capable of lasting for months or even years. Therefore allowing the enemy bolster their army and attacking, and potentially whipping out, the relatively small besieging force.