The two curving ports sit on either side of the heavy masonry of the 13th-century Château Royal, place de 8-Mai-1945 (tel. 04-68-82-06-43). It's of interest in its own right for its medieval fortifications and overall bulk, but between the months of May and September, it's also the home to a changing series of special (temporary) exhibitions, each of which comes and goes at regular intervals. Entrance fees are 4€ ($5.20) for adults, 2€ ($2.60) for students and children ages 12 to 18, and free for children under 12. In June and September, the château is open daily 10am to 6pm, July to August daily 10am to 7pm, and October to May, daily 9am to 5pm.
Also try to visit the Musée Jean-Peské, route de Port-Vendres (tel. 04-68-82-10-19), home to a collection of works by artists who painted here. It's open in July and August daily 10am to noon and 2 to 7pm; September to June Wednesday through Monday 10am to noon and 2 to 6pm. Admission is 2€ ($2.60) for adults, 1.50€ ($1.95) for children 12 to 16 and students, and free for children under 12.