Leaning Tower of Pisa (Elevation) Piazza dei Miracoli, Pisa — completed 1372 The freestanding bell tower of the Pisa Cathedral complex, begun in 1173 and completed in three campaigns over nearly two centuries. Six tiers of blind arcades wrap a cylindrical core in white marble, each storey a variation on the Pisan Romanesque vocabulary established by the cathedral itself. The famous inclination, the result of unstable subsoil discovered during the second storey, was accommodated rather than corrected — successive builders curving the upper tiers to compensate, embedding the lean into the geometry of the structure. Bonanno Pisano, attributed.