Reculver
This led the Romans to build a small fort there at the time of their conquest of Britain in 43 AD , and , starting late in the 2nd century , they built a larger fort , or "castrum" , called "Regulbium" , which later became one of the chain of Saxon Shore forts . 
<triplet> Regulbium <subj> "castrum" <obj> instance of <subj> Saxon Shore <obj> part of