According to a sign at the summit, it is possible to view the second greatest surface area seen from any peak in the world, exceeded only by the 19,340 foot (5,895 m) Mount Kilimanjaro in Africa.[15] This myth was promulgated by early real estate promoter Robert Noble Burgess, who built the first auto roads to Diablo's summit, as a draw to his Mt. Diablo Estates project, c. 1914-1917. The Mt. Kilimanjaro qualifier was first added in the 1928 Standard Oil Bulletin, which described the new Standard Diablo (SD) Tower.

According to a sign at the summit, it is possible to view the second greatest surface area seen from any peak in the world, exceeded only by the 19,340 foot (5,895 m) Mount Kilimanjaro in Africa.[15] This myth was promulgated by early real estate promoter Robert Noble Burgess, who built the first auto roads to Diablo's summit, as a draw to his Mt. Diablo Estates project, c. 1914-1917. The Mt. Kilimanjaro qualifier was first added in the 1928 Standard Oil Bulletin, which described the new Standard Diablo (SD) Tower.

The lack of surrounding peaks does indeed give the intimidating mountain an immense view. However, Diablo's relatively low height and the curvature of the earth limit the visible horizon over the sea and surrounding plains to approximately 78 miles (125 km). Beyond that, only ridges are visible and then only on their appropriately facing sides. Many higher peaks around the world offer greater general viewing distances over seas and flat plains.

One calculation shows that the viewshed from Mount McKinley (Denali) in Alaska is about three times greater. Nor is it plausible that more viewable area can be seen from the Diablo summit than any other peak in the lower 48 states. The viewshed east from Colorado summits (e.g. Pike's Peak) over the Great Plains is much greater. See the panorama external link at the foot of this page.