Ancient cultures used both natural and man made rocks and stones for building up practical and cultural buildings, different formations with questionable functions, carvings for indicating events or marking locations, and for supporting the communication between people and people, as well as people and gods.
Types of stone formations, their names and functions are introduced and discussed in a series of websites, Wikipedia itself has a wide range of collection from geoglyphs, petroglyphs, dolmens, etc. We enlisted some interesting and important links in this topic.
Aboriginal stone arrangements: Australia
Archaeoastronomical sites sorted by country
Australian Aboriginal Astronomy Project
Burial mounds in the United States
Kunhalom (burial mound or tumulus in Hungarian): http://hu.wikipedia.org/wiki/Kunhalom
Ley lines: http://en.wikipedia.org/wiki/Ley_line
List of archaeoastronomical sites sorted by country: ősi csillagászati építmények és alkotások országonként bemutatva
List of artefacts of archaeoastronomical significance: si csillagászati maradványok
Markawasi: http://www.robertschoch.net/Mystery%20of%20Markawasi.htm, http://www.labyrinthina.com/schneider.htm,
Medicine Wheels: gyógyító kerék
Mound builders: bucka (halom) építők
Nazca lines: http://en.wikipedia.org/wiki/Nazca_Lines, http://www.v-j-enterprises.com/peruart.html,
Rock art: http://en.wikipedia.org/wiki/Rock_Art
Southeastern Ceremonial Complex
Tumulus moulds and burrows in Europe and Asia
Water glyphs: http://www.waterglyphs.org/; http://www.wildernessutah.com/learn/waterglyphs.html