Because of the great power it emenates, the port of Rotterdam is the artist's main source of inspiration.

There she finds an abundance of forms in primarily unflexible materials such as iron and steel; anchor-winches, davit's, bolders, cranes, the poop of a ship etc. are the subjects of her prints.
In silkscreen Calis is able to achieve her full artistic potential. Graphic perfection is of paramount importance to her: all her work is hand-made in her own workshop and printed in very limited editions.

This site shows the works with subjects related to the harbour.