Agora Image: 2012.41.0806 (Section ΟΟ 490): Drain area, north, looking north. Indicated with H is the Heavy Wall parallel to Great Drain, C is the cutting in bedrock scarp for continuation of Heavy Wall. D is the Great Drain wall, x is the poros block, P is the packing stones in the back of the drain wall, I is the higher road strosis, II is the lower road strosis and P3 is Pit 3.