/usr/include/dune/grid/uggrid/ is in libdune-grid-dev 2.4.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/dune/grid/uggrid/ug_undefs.hh
/usr/include/dune/grid/uggrid/uggridentity.hh
/usr/include/dune/grid/uggrid/uggridentitypointer.hh
/usr/include/dune/grid/uggrid/uggridentityseed.hh
/usr/include/dune/grid/uggrid/uggridfactory.hh
/usr/include/dune/grid/uggrid/uggridgeometry.hh
/usr/include/dune/grid/uggrid/uggridhieriterator.hh
/usr/include/dune/grid/uggrid/uggridindexsets.hh
/usr/include/dune/grid/uggrid/uggridintersectioniterators.hh
/usr/include/dune/grid/uggrid/uggridintersections.hh
/usr/include/dune/grid/uggrid/uggridleafiterator.hh
/usr/include/dune/grid/uggrid/uggridleveliterator.hh
/usr/include/dune/grid/uggrid/uggridlocalgeometry.hh
/usr/include/dune/grid/uggrid/uggridrenumberer.hh
/usr/include/dune/grid/uggrid/uggridviews.hh
/usr/include/dune/grid/uggrid/ugincludes.hh
/usr/include/dune/grid/uggrid/uglbgatherscatter.hh
/usr/include/dune/grid/uggrid/ugmessagebuffer.hh
/usr/include/dune/grid/uggrid/ugwrapper.hh