The sculptural form seems to hide something beneath its surface, but what?

The shape resembles the remains of a piece of forest that long ago consisted of large trees.

The organically shaped surface also has associations with the spine and with organs such as the kidneys. 

500 cm wide x 500 cm long x 190 cm high

wall- and free hanging paper sculptures by Josefien Alkema
drawings (left) by Annechien Verhey