view looking SSE towards Manassas, VA

  Over 1 billion years ago the mighty Grenville mountain range once reached to over 12,000 feet and spanned from Newfoundland to North Carolina.  Over the millennia, the peaks have completely eroded and all that remains in the Virginia region are the Eastern and Western flanks now known as the Catoctin and Blue Ridge Mountains.  If the Grenvilles still existed, another 11,000 feet of mountain slope would extend up and behind the observatory – hence the name Grenville BASE Observatory.

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