One such visitor was King Alfonso XIII, who used to stay in the city every summer, which is how the 'Sociedad de Futbol' (Football Society) came to be called the 'Real Sociedad' (Royal Society) in 1909.
Significance. La Fortaleza (The Fortress) was the first true fortification in San Juan, established in 152l. The Spanish built it between 1533 and 1540 for protection against raids by Carib Indians and by English and French freebooters.