Devil's Highway (Roman Britain) From Calleva, this road divided into routes to various other points west, including the road to Aquae Sulis (Bath); Ermin Way to Glevum (Gloucester); and the Port Way to Sorviodunum (Old Sarum near modern Salisbury). After the Roman conquest of Britain in 43 AD an earlier Iron Age settlement developed into the Roman town of Calleva Atrebatum. It was slightly larger, about , and was laid out along a distinctive street grid pattern. The town contained a number of public buildings and flourished until the early Anglo-Saxon period. A large mansio was situated near the South Gate, consisting of three
Aphanizomenon flos-aquae samples exceeded the safety value of 1 µg microcystin per gram. University professor Daniel Dietrich warned parents not to let children consume "A. flos-aquae" products, since children are even more vulnerable to toxic effects, due to lower body weight, and the continuous intake might lead to accumulation of toxins. Dietrich also warned against quackery schemes selling these cyanobacteria as medicine against illnesses such as attention deficit hyperactivity disorder, causing people to omit their regular drugs. A Canadian study studying the effect of "A. flos-aquae" on the immune and endocrine systems, as well as on general blood physiology, found that eating