I probably shouldn't let things like this bother me, and first world problems and all that, but to see folks use Shenandoah as a plural has become my equivalent of nails on a chalk board for me.
There is the --
Town of Shenandoah in Page County and the County of Shenandoah
The Shenandoah River, and the North Fork and the South Fork
Shenandoah Valley, and Shenandoah Mountian
And Shenandoah National Park
But there are no Shennies and no Shenandoahs. We do not use a plural -- it is just simply Shenandoah.
And I'll get off my soap box now and go back to the corner...