This three-story brick and stone building, with its visually arresting facade, is one of the best surviving examples of Romanesque Revival architecture in Portsmouth. Designed by local architect and builder Edward Overman, Pythian Castle was built in 1897-98. Typical of the period’s fraternal lodges, the exotic edifice housed the meetings of the Knights of Pythias, a secret organization. It and similar fraternal societies were normally the chief patrons of such stylistically conspicuous late-19th-century buildings, usually the most elaborate structures in their communities. The “Castle” is located in the Downtown Portsmouth Historic District.