For philosophers, historians and theologians from many faiths, the greatest Spanish Jewish thinker of all time is unquestionably Moses ben Maimon, also known as Maimonides (1138-1204). Hailing from the medieval Cordoba, the prolific Maimonides championed, among other things, the school of religious rationalism. We credit him with writing the first codification of Jewish law, authoring the Yigdal chant and creating the concept of the 613 commandments - among a slew of other accomplishments. Today he is one of the most widely studied Jewish scholars and remains a household name among Jews worldwide.

But the local government of Girona, a small medieval Catalonian city some 500 kilometers from Cordoba, recently decided to pay homage to Maimonides' most famous critic, Rabbi Moses ben Nahman, or Nahmanides (1194-1270). And now, thanks to a restoration project bearing his name, the town (which is bereft of any Jewish life at all) now boasts one of the best-preserved medieval Jewish quarters in Europe.

Superficially, Maimonides and his Catalonian rival seem almost confusingly alike. The former is called Rambam, an acronym for Rabbi Moses ben Maimon, and the latter is Ramban, Rabbi Moses ben Nahman. Both lived around the same time in medieval Spain, studied rabbinics and medicine, fled their home country because of anti-Semitic persecution and died in the Middle East past the age of 65. Perhaps both have been called "the greatest Moses since Moses."

Yet while Maimonides maintained a logical, rationalistic approach to religious texts, Nahmanides stressed the miraculousness of the stories. Maimonides taught that the texts must be interpreted, or reinterpreted, to match scientific facts. Nahmanides criticized this view, believing that earthly affairs do not necessarily conform to any natural order, and that divine powers do not have to operate according to scientific laws.

Apart from writing the first Torah commentaries that incorporate kabbalistic mysticism, Nahmanides claims fame for successfully defending core beliefs of Judaism against the converted Jew Pablo Cristiano in the famous Dispute of Barcelona in 1263. Despite Nahmanides' apparent victory, however, subsequent backlash and persecution from Christians forced him to flee his beloved Girona in 1266.

Now Nahmanides' Catalonian name, Bonastruc ca Porta, symbolizes a massive restoration of Girona's medieval Jewish Quarter, as well as an educational project to teach about Girona's history as a center of medieval kabbalistic thought. The site of his house is a city monument, and the Bonastruc ca Porta Center for Jewish Studies includes a library with medieval Jewish documents, the Institute for Sephardic and Kabbalistic Studies and the Museum of the History of the Jews of Catalonia.

But why is Girona, which currently claims no practicing Jewish inhabitants, celebrating its Sephardic heritage now?

The Catalonian people always have taken pride in the characteristics of their culture and history that distinguish their province from the rest of Spain. Since the 1975 death of dictator Francisco Franco, who denied Catalonia the autonomy it craved, and forbade official and public usage of the Catalan language during his 36-year reign, the province has relished the recovery of its identity during the last 30 years. As the Bonastruc ca Porta Project, spearheaded by Joaquim Nadal, reveals, the medieval Jews of Catalonia are an integral part of that identity.

In Catalonia, the Jewish quarters are referred to as the Call. Girona's Call, an antiquated stone maze of narrow streets and steep inclined walkways, had 800 to 1,000 inhabitants from the 13th to the 15th centuries. Initially, the Jews lived in relatively peaceful relations with Christians and Muslims, but as 1492 loomed nearer, anti-Semitic prohibitions made the Call a marginalized neighborhood of reclusion.

After the expulsion of Spain's Jews in 1492, the old Jewish Quarter of Girona was sealed off, its stone archways and twisting cobbled alleys buried for almost 500 years. During the 16th, 17th and 18th centuries, Spaniards built apartments on top of the old city, moving out en masse when a new part of town developed.

Then, in the 1970s, when the Old City regained its real estate appeal, people like Jose Tarres began excavating some of the buildings. Tarres essentially discovered Nahmanides' house and sold the property to the city in 1987.

These excavations led to the Bonastruc ca Porta (Nahmanides) Project, restoring buildings and uncovering artifacts and manuscripts, some 1200 documents. Rabbis and scholars flocked to Girona to analyze the parchments, which included commentary on the Talmud, accounts of domestic life and a description of the synagogue.

This research has revealed the names of Jews who chose to convert to Christianity instead of fleeing Girona in 1492. Some citizens of Girona share variations of these names, suggesting that the Nahmanides Project could help educate the people of Girona about Jewish roots they never knew they had.

At least one person has become inspired to trace his roots all the way to Nahmanides: Ben Nahman of California. Owner of a Sephardi genealogy Web site, he has published online a list of medieval Spanish Jewish surnames, as well as the history of his own family.

About the excavations, Tarres told Nahman: "We knew when we saw the buried arches in the cellar or below ground of our original diggings that we had uncovered something of great importance. Not only for us, not only for Girona, not only for the Jews but for Catalonia, for Spain and for history."