Offa's Dyke

Offa's Dyke, an entrenchment and rampart between England and Wales, 100 m. long, extending from Flintshire as far as the mouth of the Wye; said to have been thrown up by Offa, king of Mercia, about the year 780, to confine the marauding Welsh within their own territory.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Oesel * Offenbach, Jacques
Odyssey
Œcolampadius, Joannes
Œdipus
Œhlenschläger, Adam Gottlob
Oehler, Gustav
Œil-de-bœuf
Œland
Œnonë
Oersted, Hans Christian
Oesel
Offa's Dyke
Offenbach, Jacques
Offertory
Ofterdingen, Heinrich von
Ogham
Oglethorpe, James Edward
Ogowe`
O'Groat's House, John
Ogyges
Ogygia
Ohio