Sudbrook, Monmouthshire the Silures from the 2nd century BC and occupied by the Romans from the 1st century AD until the 4th century. The hillfort was originally much bigger than now having been eroded over the centuries. Finds of Roman coins at Black Rock, Portskewett, show that the ferry crossing was in use in Roman times, on the route between the Roman stations of "Aquae Sulis" (Bath) and "Venta Silurum" (Caerwent). According to tradition, Caradog Freichfras, the Welsh ruler of Gwent in the 5th century or 6th century AD, moved his court from Caerwent to the Portskewett area, possibly to the fort.
Aphanizomenon flos-aquae it had a profound effect on natural killer cells (NKCs). "A. flos-aquae" triggers the movement of 40% of the circulating NKCs from the blood to tissues. Some compressed tablets of powdered "A. flos-aquae" cyanobacteria (named as "blue green algae") have been sold as food supplements, notably those filtered from Upper Klamath Lake in Oregon. Aphanizomenon flos-aquae Aphanizomenon flos-aquae is a brackish and freshwater species of cyanobacteria found around the world, including the Baltic Sea and the Great Lakes. "Aphanizomenon flos-aquae" can form dense surface aggregations in freshwater (known as "cyanobacterial blooms"). These blooms occur in areas of high nutrient loading,