English: Damage believed to have been caused by a blast of artillery-fire from the guns of Oliver Cromwell in 1650. The owner, John, 10th Lord Borthwick, a supporter of the Stuarts, surrendered before the castle suffered further damage.

"To the Governor of Borthwick Castle there. Sir, I thought fitt to send this trumpet to you to lett you know, that, if you please to walk away with your company, and deliver the house to such as I shall send to receive it, you shall have liberty to carry off your armes and goods and such other necessaries as you have. You have harboured such parties in your house as have basely unhumanely murdered our men; if you necessitate me to bend my cannon against you, you must expect what I doubt you will not be pleased with. I expect your present answer, and rest your servant, O. Cromwell"