Upper Street in Norfolk isn't actually a street as the name suggests, it's a small hamlet of houses and also a section of the A1062 rural main road which links Hoveton and Potter Heigham and runs past the outskirts of Horning village in the Norfolk Broads area. Following the country lanes from Upper Street down to the Ferry Marina will take you into Horning itself, where the one road through the village is called, unsurprisingly, Lower Street.
During my travels around Norfolk and north Suffolk over the last few years I've walked along or driven down many lanes, avenues, streets and roads with names which obviously haven't needed much thought or logic. The Avenue is a fairly common one and Back Lane is exactly that. Then there's The Green where there isn't one, and not far from the site where I camp at California there's The Promenade and The Esplanade, though neither of them are adjacent to the sea. Beach Road is another common one, I think every coastal town and village in Norfolk has one which obviously leads to a beach. There's also an Upper Street and Lower Street in Suffolk - I haven't been to either of them yet but there's always time!
I've often wondered who was originally responsible for giving these various places such simple names; whoever they were they mustn't have had much imagination - or maybe they just took the easy way out.