My impression was that they were assembled on site, but they were pre-made and could be dissembled. From this thread, it looks like both methods could have been

My impression was that they were assembled on site, but they were pre-made and could be dissembled. From this thread, it looks like both methods could have been used: https://www.reddit.com/r/AskHistorians/comments/3z597l/in_medieval_warfare_how_were_catapults_trebuchet/ https://www.reddit.com/r/AskHistorians/comments/3z597l/in_me...