Aldbar Cross SlabAldbar Cross Slab. The Aldbar Stone, a Pictish cross slab of 9th century origin, comes from the burial ground of the church at Aldbar, a few miles from Brechin. It is sculptured on both sides. The front side of the six foot stone has a full length Celtic Cross intricately carved with interlaced knotwork and key patterns. The cross is flanked by two staring cleric's holding books. The endless knotwork design represents eternal life. The outer circle