Wemyss Castle originally consisted of a 15th-century rectangular tower and a large irregularly shaped courtyard, with a round tower at one corner, which may date from the 13th century or earlier. Ranges of buildings were built within the courtyard in the 16th century, and in about 1699 a large L-plan block was also added. The castle was extended again, and the courtyard was finally filled in during the 19th century. Most of the Victorian additions were demolished in the 1930s, and the castle was restored back to something like its original appearance.