I'll write down what's on the information panel for those who can't see it:

"This square bears the name notable statesman Ricardo Alegría to whom, Puerto Ricans and all other non-Puerto Ricans that have fallen in love with our island, are eternally indebted for this rescue, protection, and preservation of the beautiful and historic peninsula that we all know as Old San Juan, "Elite historic city of the Americas".

Ricardo E. Alegría
Born April 14, 1921

Thanks to him, we can enjoy walled city and its cobblestoned streets. Guardian angel of Puerto Rican culture, and patrimony and above all, Old San Juan.

Some facts about this notable national hero:

• Puerto Rico's first professional anthropologist.
• B.A., 1942 University of Puerto Rico, M.A., 1947, University of Chicago : Ph.D., 1954, Harvard University.
• As an historian of Puerto Rico folklore, archaeologist, and educator, Alegría has written more than 25 books of these subjects of more than 1000 newspaper articles and commentaries on Puerto Rican culture, history, and societal tendencies.
• Member of the Society of America, Real Academy of History in Madrid, and the Puerto Rican Academy for the Spanish Language.
• Recipient of numerous honorary doctorate degrees from distinguished universities. The National Academy of Arts and Sciences, Literature Institute of Puerto Rico, National Trust for Hispanic Preservation, American Association for State and Local History (Cooperstown), Anthaeum of Puerto Rico, American Society of Travel Writers, Broadcaster Association of Puerto Rico, The Central Cultural Pablo de la Torriente Brau of Havana, and Puerto Rico Chamber of Commerce are amongst the many institutions that have awarded Alegría's work.
• Alegría's also was the first Latino to be honored by the Smithsonian Institution. Other institutions to honor Alegría include the U.S. House of Representative, New York's Museo del Barrio, and the San Juan Festival.
• Among his numerous recognitions, Alegría has received the Spanish government's Silver Medal for Tourism Development, the American Historic Preservation Society's George McAneny Medal, Heraldry, Order of Christopher Columbus, (Knight), National Humanities Medal and the Charles Frankel Prize, Pablo Picasso Gold Medal (designed by Joan Miró), Medal from the Order of Duarte, Medalla Sanchez in the Dominican Republic, Order of Francisco de Miranda from Venezuela Government, Medal from the Order of Puerto Rico's Fifth Quincentennial, Gold Medal from Puerto Rican Institute of Culture, National Culture Medal (La Habana), and the renown Centenary Pablo Neruda granted by government of Chile.
• Alegría's great legacy of Puerto Rican Institute of Culture which he helped found is of immeasurable value to Puerto Rico's history and society.

Those interested in more information on Alegría may refer to Carmen Dollores Hernandez's book "Ricardo Alegría, Una Vida" published by the Centro de Estudios Avanzado de Puerto Rico and the Caribe, 2002. (First edition) or visit the following webpage: www.prte.net/centro/ ."

I don't know if the website at the bottom is gone or if I spelled it wrong. It's kind of hard to read on the picture's photo.