David,
i would think that antenna height is above ground, whether that be on 
the paciffic ocean beach or in Denver.  Otherwise, here near Chicago 
my G5RV is nearly 1,000 feet high!  i couldn't afford the feedline!
Pat, K9JAUAt 08:18 AM 4/14/2015, you wrote:
>Hi:
>
>If a person's QTH is in an elevated area(Denver, for example), which is
>nicknamed the "mile-high city", and they tell you that their hex beam is
>mounted at a height of 50 feet, it seems to me that this figure should be
>added to the QTH's elevation to have a more accurate height  Is this valid,
>or is this a faulty assumption         ?
>
>Sincerely yours,
>
>
>
>David S. Pearson-wa4dsp.
>
>
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