Displacement map to Geometry

If you have a model that uses a displacement map to create detail, and you want to turn this into actual geometry, for example for 3D printing or for sculpting further detail, it's not enough to just apply the Subdiv modifier.  Instead, mute or remove the Displacement Shader nodes.

Then add a Displace modifier and add the Displacement Texture to it. Use the UV map as the coordinates and reduce the strength as needed.  Also, make sure that the scale of the displacement mapping matches that of the material. Finally, select the object in Object Mode.

Press Ctrl+A and choose Visual Geometry to Mesh.  This  applies the Displacement and Subdiv modifiers. And now the Displacement is baked into the geometry.