The high inland parts of a country — the hills and high open ground, away from the sea and above the flat farmland. This plural form is the one people actually use when they are talking about a real place or region: "the uplands of Scotland", "farming in the uplands", "the birds return to the uplands in spring".

It takes a plural verb: "the uplands are cold in winter." And it usually comes with 'the'. The plural does not mean several separate hills you could count — it names a whole stretch of high country as one area, the same way we say 'the tropics' or 'the plains'. This is why you cannot say 'two uplands'.

The feeling of the word is open, empty, and a little hard: thin soil, sheep rather than crops, small villages, weather that arrives fast. Nature writers love it. Government reports on agriculture use it constantly, because upland farms need different rules and different help from lowland ones.

It is a fairly formal, written word. Talking to a friend you would more likely say "up in the hills".