land art

On Google images:
british "land art" - Google Search

An introduction:
Land art - Wikipedia, the free encyclopedia

Andy Goldsworthy:

Andy Goldsworthy creates ephemeral Land Art with natural materials found in the wilderness | Inhabitat - Green Design, Innovation, Architecture, Green Building

Chris Drury:

Chris Drury

David Nash:

Ash Dome: A Secret Tree Artwork in Wales Planted by David Nash in 1977 | Colossal
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