Abstract: A concrete building block (10) having a top (12), a bottom (14), substantially identical first and second end portions (16, 18) and a central portion (20). First and second end portions (16, 18) each have a connector pin (28, 34) and a complementary connector socket (30, 36), where each connector pin and connector socket generate about a vertical axis of generation (A1, A2). The block (10) also includes a lifting eye (46) that projects upwardly from a well (50) and a decorative surface (56) of vertical ridges and valleys on at least the first side (22), and a first and second end surfaces (26, 32). An alternate block (11) includes a circular top (58), a circular bottom (60), and a sidewall (62). Block (11) also includes a connector pin (64), a complementary connector socket (66) and a vertical axis of generation A3, of which connector pin (64) and connector socket (66) generate about, and a means for engaging block 11 with a lifting device.