Definition of «high plateaus»

The phrase "high plateaus" refers to flat or level areas of land that are situated at high altitudes or heights.

Have stocks reached «a permanently high plateau»? (thereformedbroker.com)
It doesn't sound like no global warming, it sounds like we had a very high plateau and now 2014 and 2015 we are going back up the staircase again. (rabett.blogspot.ru)
That is, I allow for the possibility that we really have reached a permanently higher plateau. (early-retirement-planning-insights.com)
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