On the chart Transgressing this area, starting near Tacitus, than southward, and southeastward the Altai escarpment bright when sun light comes in from the east. Also on the chart, crossing the craters Polybius A and Polybius B, starting at Tycho we see a bright ray. (Chart 64). The big crater Catharina forms a striking triplet with craters Cyrillus and Theophilus. (Chart 46).
Escarpment. (Length: about 427 km) (24.3°S, 22.6°E,) (Height: 1000m /3000ft) Escarpment more or less abruptly staring near Catena Albufeda in the North than going south to Piccolomini. South-East North-West oriented. In form of a great arc, forming the edge of Mare Nectaris.
Walled plane (104Km /61Mi ø ) (Height: 3130m /9500ft)(Height:3,130m) (18.0° S , 23.6° E) Eroded circular formation forming a North-South aligned trio with Theophilus and Cyrillus. Steep slopes, Eroded to the north-east and supporting Catharina D to the north-west Catharina A to the south-west and Catharina C to the south-east. High walls to the south-east crushed by the large ghost semi crater Catharina P to the north by Catharina B & G to the north-east and by the crater Catharina S to the south. Flat floor to the East and jumbled to the west. Craterlets crack and hills.
Crater. (42km/25Mi ø ) (Height: 2,050/6200ft) (22.4°S, 25.6°E) Isolated circular formation, steeper slopes to the East supporting a chain of craterlets to the north and many craterlets all around, high walls ridden by craterlets to the south-west. Flat floor filled with lava and Craterlets.
Crater. (40km/24Mi ø ) (Depth: 2,840/8600ft) (16.2°S, 19.0°E) Steep slopes supporting a craterlet to the north-west, Tacitus N and 2 craterlets to the south-east. High walls supporting 2 craterlets to the north. Small lengthened central relief and a craterlet to the south.