The presumptive but unlikely site of Pedro de Mendoza’s founding of the city, famed landscape architect Carlos Thays’s Parque Lezama is an irregular quadrilateral above the old river course (now covered by landfill). Shaded by mature palms and other exotic trees and studded with monuments, it’s the place where aging porteños play chess, working-class families enjoy weekend picnics, and a Sunday crafts fair stretches along Defensa to Avenida San Juan.

On the capital’s southern edge in colonial times, the property came into the hands of Carlos Ridgley Horne and then Gregorio Lezama, whose widow sold it to the city in 1884. Horne built the Italianate mansion (1846) that is now the national history museum; at the northwest entrance, Juan Carlos Oliva Navarro finished the Monumento a Don Pedro Mendoza (1937) a year too late to mark the 400th anniversary of Buenos Aires’s original founding.

Opposite the park’s north side, architect Alejandro Christopherson designed the turquoise-colored onion domes and stained-glass windows of the Iglesia Apostólica Ortodoxa Rusa (Russian Orthodox Church, 1904, Avenida Brasil 315), built with materials imported from St. Petersburg.