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 (dietary supplement) and sun exposure can greatly affect lipid and pigment composition. As more is learned about the components of different cyanobacterial species, growers and harvesters are better able to determine the optimal growth conditions for obtaining optimal yields. " Aphanizomenon flos-aquae" has been shown to contain varying amounts at least 13 vitamins: vitamin A (beta-carotene), vitamin C (ascorbic acid), vitamin E, vitamin K, and many of the B-complex vitamins including B (thiamin), B (riboflavin), B (pyridoxine), choline, biotin, niacin, folic acid, pantothenic acid, and B (cobalamin). However, "Aphanizomenon flos-aquae" contains pseudovitamin B which can block absorbtion of true B and is