A long travel aerostatic linear stage includes a plurality of rails, a plurality of planar bearing plates, and a plurality of porous media gas bearing. The plurality of planar bearing plates are aligned with and attached to the rails. Each planar bearing plate includes a plurality of metal plates having machined air bearing surfaces. The plurality of porous media gas bearings float on the bearing plates in a non-contact frictionless manner to support a traversing load and control lateral motion of the rails. The rails may include at least one rail which supports the traversing load and at least one rail which controls the lateral motion. The bearing plates are restrained and attached to the rails in a manner that ensures the planar nature of the bearing plates are maintained and the air gap is effective.