V, a programme of construction hitherto unparalleled was begun in level IV. Thereafter, the buildings were vastly larger than earlier, some had novel designs and new construction techniques were used for the structure and the decoration. Level IV of the Eanna is divided into two monumental groups: in the west, a complex centred on the 'Temple with mosaics' (decorated with mosaics made of painted clay cones) of level IVB, subsequently covered by another building (the 'Riemchen Building') of level IVA. To the east there is a very important group of structures—notably a 'Square Building' and the 'Riemchen Temple Building', which were subsequently replaced by other buildings with original plans, like the 'Hall with Pillars' and the 'Hall with Mosaics', a square 'Grand Court' and two very large buildings with a tripartite plan, 'Temple C' (54 x 22 m) and 'Temple D' (80 x 50 m, the largest building known from the Uruk period). The second monumental sector was attributed to the god Anu by the excavators of the site, because it was the location of a sanctuary for this god some 3000 years later. It is dominated by a series of temples built on a high terrace after the Ubayd period. The best-preserved of these is the "White Temple" of level IV, which measures 17.5 x 22.3 m and gets its name from white plates that covered its walls. At its base, a building with a labyrinthine plan, called the 'Stone building', was built. The function of these buildings, which are unparalleled in their size and the fact that they are gathered in monumental groups, is debated. The excavators of the site wanted to see them as 'temples', influenced by the fact that in the historic period, the Eanna was the area dedicated to the goddess Inanna and the other sector was dedicated to the god An. This conformed to the theory of the 'temple-city' which was in vogue during the inter-war period. It is possible that this is actually a place of power formed by a complex of buildings of different forms (palatial residences, administrative spaces, palace chapels), desired by the dominant power in the city, whose nature is still unclear. In any case, it was necessary to invest considerable effort to construct these buildings, which shows the capacities of the elites of this period. Uruk is also the site of the most important discoveries of early writing tablets,