The municipality of Alajuela is also a major tourist attraction. In the center of the city is a centuries-old cathedral with a plaza where mangoes regularly fall from the trees. Known as "The City of Mangoes," there is a mango festival each June. Next to the plaza, there is a museum dedicated to folk hero Juan Santamaría. This museum is located within the old Alajuela Prison building and as of 1999 encompasses the old city armory, both of which are buildings constructed on the second half of the 19th century. One wing of that museum revives the history behind the Battle of Santa Rosa between Costa Rica and American filibusterer William Walker in 1856, while other sections feature relics and displays from around the country. The museum also portrays the local culture, dedicating a section to local artisans and their works, and public theater events such as plays and lectures.