After visiting the Cámara Oscura on the northeast corner of the plaza (daily 9:30 a.m.–7 p.m., CUC2), begin your clockwise tour by following the shaded arcade along the plaza’s east side. Midway, you’ll pass the Casa de Juan Rico de Mata, today the headquarters of Fototeca (Mercaderes #307, tel. 07/862-2530, fototeca
@cubarte.cult.cu, Tues.–Sat. 10 a.m.–5 p.m.), the state-run agency that promotes the work of Cuban photographers. It offers international photo exhibitions in the Salón Nacional de Fotografía. Note the ceramic wall mural designed by Amelia Peláez.

Next door, the Planetario Habana (Mercaderes #309) opened in February 2010 as a cultural center for science and technology, with a 66-seat planetarium displaying 6,500 stars, interactive exhibitions about the universe, and a computerized library. The four-level museum tops out with a state-of-the-art Goto telescope.

The old Palacio Vienna Hotel (also called the Palacio Cueto), on the southeast corner of Plaza Vieja, is a phenomenal piece of Gaudí-esque art nouveau architecture dating from 1906. At last visit it was being restored as a deluxe hotel.

Moving to the south side, the Casa de Marqués de Prado Amero today houses the Museo de Naipes (Museum of Playing Cards, Muralla #101, tel. 07/860-1534, Tues.–Sat. 8:30 a.m.–5 p.m., Sun. 9 a.m.–2 p.m., entrance by donation), displaying playing cards through the ages.

On the plaza’s southwest corner, call in at the Casa de los Condes de Jaruco (House of the Counts of Jaruco, Muralla #107, Tues.–Sat. 9 a.m.–5 p.m.) to view the various art galleries, then cross San Ignacio and follow Muralla half a block to the Tienda El Soldadito de Plumo (Muralla #164, Mon.–Fri. 9 a.m.–5 p.m., Sat. 9 a.m.–1:30 p.m.), selling miniature soldiers made of lead! A large glass window lets you watch artists painting the pieces.

Return to the plaza, turn left to follow San Ignacio north, and cool off with a chilled beer brewed on-site in the Taberna de la Muralla (San Ignacio #364, tel. 07/866-4453, daily 11 a.m.–1 a.m.), in the former Casa del Conde de Casa Lombillo. The copper stills are displayed in the main bar, where a 1913 Ford delivery truck now sits and artworks by such famous Cuban artists as Kcho and Nelson Domínguez are displayed.

Fifty meters to the north, the Casa del Conde de San Estéban de Cañongo (San Ignacio #356, tel. 07/868-3561, Mon.–Fri. 9:30 a.m.–5:30 p.m., Sat. 9:30 a.m.–1 p.m.) opened in 2009 following restoration as a cultural center. Adjoining, on the northwest corner of the plaza, is the Casa de las Hermanas Cárdenas, recently restored and today housing the Centro de Desarollo de Artes Visuales (San Ignacio #352, tel. 07/862-2611, Tues.–Sat. 10 a.m.–6 p.m.). The inner courtyard is dominated by an intriguing sculpture by Alfredo Sosabravo. Art education classes are given on the second floor, reached via a wide wooden staircase. The top story has an art gallery.

Well worth the side trip is Hotel Raquel (San Ignacio, esq. Amargura, tel. 07/860-8280), one block north of the plaza. This restored hotel is an art deco and neoclassical jewel.