"high terrain" is a correct and usable phrase in written English.
You could use it to describe a hilly area or land that is at a high elevation. For example, "The terrain in the mountains was high and rocky, making the hiking difficult."
Gravel for roads was quarried from the high terrain by Cherry Valley Avenue.
The high terrain would have helped the ice sheet to establish and persist.
In the high terrain of the western North Carolina, 10 to 15 inches are likely with localized higher amounts.
Eventually, radio beams were used to create a national network of airways to link major cities and define safe corridors through high terrain.
At the western edge of Dartmoor high terrain that rises in exposed granite peaks gives way to the gentle swell of undulating farmland.
Satellite images showed that Maria became disorganized, without a defined eye, and weakened as it moved slowly across the high terrain of Puerto Rico.
For purposes of clause (iii), the term "high terrain area" means with respect to any facility, any area having an elevation of 900 feet or more above the base of the stack of such facility, and the term "low terrain area" means any area other than a high terrain area.
The dam area of the SUOXI hydropower project shows high terrain undulation and complex geological conditions, containing 6 faults and 7 weak inter-beds.
The Walsers were German-speaking refugees and migrants who spread south through the Alps during the Middle Ages, improvising a life style on the high terrain where nobody else farmed or lived.
Situated between the Mountains of Mourne on one side and Slieve Gullion, the high terrain of South Armagh, on the other, Newry has just topped the poll in rising property prices across the UK.
