Jo wrote: > #3 0xb7884ee6 in geos::geom::CoordinateArraySequence::getAt (this=0x0, > pos=7117) Ensure your sequence has at least 7117 + 1 elements. The asserts come from here: http://trac.osgeo.org/geos/browser/trunk/source/geom/CoordinateArraySequence.cpp#L134 Best regards, -- Mateusz Loskot http://mateusz.loskot.net