Repeated sightings of similar UFO's over a period of years always landing at one sight.

Approx. 9.30 - 10pm, Saturday evening, coming from northerly aspect heading south, object descended behind mountain to where the local tip (garbage dump site).
 This was one of MANY occassions when myself and family members and neighbours saw similar objects, always heading in the same direction, always "landing" at the same sight.
 The variances were that on some occassions:- the craft would appear and travel at an extremely fast speed and then halt suddenly (but smoothly) and descend slowly; other occassions the craft would 'drop' suddenly, and the craft would be dark; on other occassions the craft would hover and eminate a bright light and 'land'  Some sightings lasted a matter of 10 seconds, others for several minutes.
 The crafts were the shape of two saucers placed on top of each other; and were a mid-grey/greenish colour, a matt finish.  A dull yellowish light formed a tail when the crafts were travelling, however whenever the crafts hovered the yellowish light emited from beneath.
 Our house was approx. 1 mile from the landing site, and from this distance, it looked as though the craft were 12' in diametre and 10' high and 40' round.  The "saucer" had a spinning motion.  I did not see any windows on any of the craft.
 Why "we" have believed these were UFO is because of the movement/action of the craft - the sudden "take off", the hovering etc were not possible by helicopters, aeroplanes, or 'falling stars' or meteorites.
 The craft always descended in the same area.
 We wonder whether they landed in the tip on the large, flat-ish surface; or whether they landed in the mountain.
    Interestingly, we have later learned that there a series of markings in caves similar to heiroglyphs.  And there are two other areas with similar markings and when plotted on a map, form the shape of a pyramid.
Witness indicates that the date of the incidents are approximate.  PD