Beginners series Episode 4: Planters,seeders,potato planters and ridge markers, guide to planting - YouTube
TUTORIAL - How to use RIDGE MARKERS - Farming Simulator 19 - FS19 Ridge Marker Tutorial - YouTube
Collar Ridge Marker Stone Marker Stone : The Megalithic Portal and Megalith Map:
File:Sweeney Ridge, Portola Discovery Site marker. "From this ridge the Portola expedition discovered San Francisco Bay November 4, 1769" - panoramio.jpg - Wikipedia