One of the most widely used books of Jewish law and one of the most influential schools of Jewish mysticism were both produced in Safed within the same few decades, by people who knew each other.
A law code written here
Joseph Karo, working in Safed in the sixteenth century, compiled the Shulchan Aruch, a systematic code of Jewish law that went on to become one of the most widely accepted legal references in subsequent Jewish practice across many different communities, an outsized influence for a text produced in a relatively small hill town.
A mystical system taught here
In the same period, Isaac Luria arrived in Safed and taught a distinctive system of Kabbalistic thought, dying only a few years later; his teachings survive mainly because his student Chaim Vital wrote them down, since Luria himself left little in his own hand. Luria's cosmology, addressing creation, exile and repair, became hugely influential in later Jewish mysticism largely through Vital's transcriptions rather than any text Luria authored directly.
A community reduced by disaster
Safed's Jewish community, which had grown substantially around this concentration of scholars, was devastated by a major earthquake in 1837 that killed a large portion of the population and destroyed much of the town, a disaster from which the community's earlier scale never fully recovered even as the town's mystical legacy continued to draw scholars and visitors long afterward.