Southsea Castle is a historic fortification in Portsmouth originally built by Henry VIII and now operates as a free museum with seasonal hours from April to October. The castle features a central keep with interior exhibits, ramparts for exploration, a film room, and panoramic viewing areas offering vistas toward the Isle of Wight and the Solent. Year-round amenities include a courtyard café and rooftop bar, an on-site shop, and event hosting capabilities. The castle serves as both a historical attraction and a popular venue for celebrations and private functions in the heart of Portsmouth's seafront.