Siege camps cannot be attacked.
The wave sent from the siege camp takes 1 hour to reach your village so you have a while to prepare to defend against it.
You can use either interdiction or research diplomacy to avoid enemy siege camp attacks.
Siege camps can be used to acquire large amounts of honour. The waves are relatively easy to defend against at the start of the game. You can get a few hundred thousand honour from defending against multiple siege camp waves on a few of your villages late in the game, so they can help you to rank up quickly.
The wave that hits you is dependent on what rank you are. The higher up in rank you go up the larger and more powerful the waves are that the siege camp sends at you.
A siege camp defeats you if it manages to reach your keep and results in a loss of honour.
A siege camp will send 3 waves at you. The first wave will read something like "the enemy is sending a small wave to test your defences" in the report. The second will read something like "the enemy is sending and attack against us" and the last will read something like "the enemy is sending everything they have at us". The waves get progressively stronger. The first will usually be a relatively weak wave that can easily be defended against; the second will be slightly stronger but can also be defended against easily. At higher ranks the third wave can cause a lot of damage if you don’t have a few ballista in your castle and a lot of archers because there will be a reasonable number of catapults in the wave.
Crown Prince Siege Camp Waves
Reaching crown prince means siege camps reach a new level of challenge for you. They send around 900 troops in the final attack wave which includes s decent number of catapults. You must ensure to have fully built castles with the maximum number of ballista and turrets as well as making sure you have your archers placed in effective positions of your towers. The sheer number of troops means that if your castle is not built properly they can inflict heavy damage on you. However if you have your castle built strong you can defeat these waves losing only a dozen or so archers and no towers whatsoever. The wave pictures here results in over 51,000 honour for defeating it meaning you can gain quite a bit of honour from defending against these waves.