Early crossroads trails were camped by many different people and species. The reason they were pivotal was because of access to many things. Shelter, vision, dreams, game, water, medicines, nutrients, etc.

An ancient site known still has many of these things today.

Water is key ingredient to lift the veil of calcium. That is usually for black color emerging as red is easier to see through calcium. Although black is older form of ink. Black on stone is also seasonal water falling pathways on cliffs. Flash flood trails. Pictographs writing in origins says where there is spirit writing.