SPFX DEPT.

The Colossus from THE COLOSSUS OF RHODES (1961) 

THE COLOSSUS OF RHODES utilized a panoply of special effects and image trickery and big practical effects to bring the Colossus to life.

Above: standard model of the statue. The model was used for complicated shots that would have been too difficult to recreate with full scale effects. For example, in this scene, fire is released from the cauldron. 

 

In this scene, we see actors walking on the statue which means this was a full size replica of the statue. There are plenty of 'behind the scenes' photos of this big statue.

In this scene, Rory Calhoun walks in the foreground with the statue in the background. The statue was composed of two parts: bottom part was a full scale replica while the top half, the part which Rory's head didn't cross, is either a matte painting or a model to scale. Notice the reflection in the water. We see the legs reflected but they placed a barrel to hide the fact that there's nothing beyond the legs. 

In this shot, we see the full scale feet of the statue in the background, giving this incidental scene a lot of realism.