Todd Bolen/

TWO ROADS DIVERGED. The sixth-century C.E. Madaba map shows two major north-south thoroughfares (called cardos) in Byzantine Jerusalem—both originating at the plaza in front of Damascus Gate in the north (at left). The lower, western Cardo runs through the center of the city, past the red-roofed Church of the Holy Sepulchre (depicted upside-down in the middle of the mosaic) toward another red-roofed church on the other side of the Cardo on Mt. Zion in the southern part of Jerusalem: the Nea Church. When was the Cardo built? The Nea may hold the answer.