On the hill above my house, where lies my allotment, there used to be a neolithic hill fort, now mostly covered by a race course and development. Nearby there is a strange, long, absolutely straight line, running almost exactly N-S, that shows up on Google Earth but is no way visible on the ground, esp. now with all the summer overgrowth:

Lat: 50°49'28.63"N
Lon: 0° 6'54.37"W

I've marked it with a place mark but I don't know whether that's only stored on my PC. The photos were obviously taken in Spring a year or so ago.

I thought it might be where 2 satellite photos don't exactly match up, maybe slightly overlapping, but the thickness and shading on the line alters, certain ground features interrupt it, and there are no other mismatches around.

FYI the allotment is very close, at:
Lat: 50°49'24.34"N
Lon: 0° 6'50.23"W

When this pic was taken there was nowt but an empty rectangle of overgrown grass. It's now covered with beds, a shed and decking, and a pond.

The hill fort was roughly at
Lat: 50°49'36.77"N
Lon: 0° 6'48.94"W

Not very obvious but there appears to be earthworks at:

Lat: 50°49'39.64"N
Lon: 0° 6'41.82"W

What do you think?