technical tuesday: how’d they do that?

From the aludean website:
 “This sculpture was hand modelled in 4 tonnes
of clay and then cast in reinforced resin. During the clay modelling
stage, studio lighting was tuned to match the final installation site to
allow adjustment of the form and control the shadows that give Voyage
its life and rhythm.

The sculpture is 14 m long, 3.6 m high and roughly 8 cm deep.”

Gorgeous…incredible….but seriously how’d they do that?