The Parallel Lines
Curiouser and curiouser....
Amador County is more populated, naturally, in the lower elevations below the snow line. On the upper end of the county, towards Tahoe, there is a phenomena that satellite photographs show is shared with Californians from Oroville to Bakersfield. The lines are precisely 3 miles apart and are expressed in a variety of ways in the topography. This effect can be seen from 10 miles above the Earth to about 40 miles. One can zoom in on these lines and observe the fact that they actually do exist in the physical landscape and are NOT a product of mapping software or glitches. Above 40 miles, however, their subtlety becomes invisible.
Other lines and grids
Of course the world famous Nazca Lines are known for their vast coverage of South American territories, but the phenomena of parallel lines, grids, and submerged features that are repeating patterns can be observed all over the Earth. What you need to locate these, is 10 spare minutes and access to a computer equipped with mapping software. Satellite imagery has made this exercise a walk in the park.