Lalibela is one of the most mature examples of architecture produced not by building but by subtraction — the medieval peak of the carved (subtractive) line that Ħal Saflieni began in prehistory. Here the church is not raised from stone blocks; it is freed from within the rock as a single piece.

The method is bold and irreversible: the masons first cut deep trenches in the red volcanic-tuff plateau that trace the outer limits of a building; a giant stone block thus emerges as an 'island' within the rock, freed on all four sides. This block is then carved top-down so that its roof, walls, windows, doors, columns, and interior volume are all sculpted from the same mass with no additions. No part of the structure is carried, added, or mortared; everything is the negative of the material removed. The most famous, the Church of Saint George (Bete Giyorgis), is — seen from above — a single buried stone block in the plan of a Greek cross.

This technique demands zero margin for error: a mistake in carving cannot be patched and corrected, because the material cannot be put back. Lalibela thus erases the boundary between architecture and sculpture — the building is a sculpture at vast scale. Conceived as a 'New Jerusalem' in the Ethiopian Orthodox tradition, this group of churches is an extraordinary monument to turning stone into space by removal, and to incising a faith directly into geology.