Mexico: Ground Traces Left By Unknown Lights, Cerro del Quinceo, Mexico (1997)
Claudio Mora of La Esfera Azul writes: "Back in 1997 there was a wave of unknown lights in the sky in the general vicinity of Cerro del Quinceo, Morelia, in the Mexican state of Michoacán. Some reports suggested that these lights had landed. We had the opportunity to visit the area in person several years later and were able to find the exact spot where ground traces of unknown origin could be located."
At minute 6:39 in the video, the speaker points out that 'between six and seven impressions' are to be found where grass will not grow, having roughly the same shape (discarded plastic bottles are removed to give a better view). "What is most striking is the circular shape of these impressions," going on to note that the surrounding grass is completely dry.
The video can be seen at https://www.youtube.com/watch?v=UZ33bU2OAFM.