I don't know why I forgot that you can do this as well : area.poly(intersect(p1,p2)) ... a bit more straightforward. greetings, Remko -- View this message in context: http://r.789695.n4.nabble.com/calculate-area-between-intersecting-polygons-tp3012980p3014581.html Sent from the R help mailing list archive at Nabble.com.