Medieval Lords, knights and their Siege Engineers identified the weakest parts of the Castle or town that they needed to attack and planned the Medieval Siege Weapon Design accordingly.

Medieval Siege Weapon Design Factors
The following elements had to be discussed and taken taken into account before arriving at the final decision for the Medieval Siege Weapon Design.

• Strength and size of the castle or town to be attacked
• Potential weak points
• The number of fighting men and the resources inside the castle
• What was the morale of the enemy like - could this be reduced further by fear and intimidation?
• The fear instilled by the massive siege weapons could help with this
• What supplies were likely to be available in the castle?
• Was there a supply route for new supplies - access to the sea? Could this prolong the siege and increase the expense involved?
• Was Fresh water readily available?
• What were the strength and types of weapons inside the castle?
• The Fortifications of the Medieval Castle - The attackers needed to identify all the weak spots of the Castle. Medieval Defences such as a Portcullis, Drawbridge, Barbican, Murder Holes and Moat would have to be surmounted with the help of siege engines
• The correct position for the siege engines had to be established to ensure maximum effectiveness with minimum casualties!
• The land surrounding the castle would be checked out to determine the local materials which were available for building the Medieval siege engines and whether they would be suitable for the Medieval Siege Weapon Design
• The size of the castle wall would determine the height and the Medieval Siege Weapon Design
• The next stage would be to estimate the length of time required to build the siege weapon
• Then the resources, in terms of man power, required to build the siege engine and ensuring that skilled Medieval siege weapon makers were available, such as carpenters and Blacksmiths, to make the parts of the siege engine
• Ensure a sufficient and the correct type of tools were available to build the Medieval siege engines
• Finally oxen had to be slaughtered to obtain wet hides necessary to cover some parts of siege weapons e.g. siege towers, to minimise casualties. Arrangements often had to be made to have them imported

The whole area outside the Medieval castle became a noisy hive of activity. The Medieval Siege Weapon Design had been finalised and the siege engines would be built! Battle plans had to be drawn - no two sieges were ever conducted in exactly the same way. During this siege weapon preparation period the attackers would seek terms of surrender with the enemy. Failure to 'Come to Terms' resulted in siege warfare and the use of the terrifying Medieval siege weapons.