/usr/include/ThePEG/Config/ is in libthepeg-dev 1.8.0-3build1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/ThePEG/Config/Complex.h
/usr/include/ThePEG/Config/Constants.h
/usr/include/ThePEG/Config/Containers.h
/usr/include/ThePEG/Config/HepMCHelper.h
/usr/include/ThePEG/Config/LWH.h
/usr/include/ThePEG/Config/PhysicalQty.h
/usr/include/ThePEG/Config/PhysicalQtyComplex.h
/usr/include/ThePEG/Config/PhysicalQtyOps.h
/usr/include/ThePEG/Config/Pointers.h
/usr/include/ThePEG/Config/TemplateTools.h
/usr/include/ThePEG/Config/ThePEG.h
/usr/include/ThePEG/Config/ThePEG_Qty.h
/usr/include/ThePEG/Config/Unitsystem.h
/usr/include/ThePEG/Config/algorithm.h
/usr/include/ThePEG/Config/std.h