A motion sickness prevention eyewear presents a demarcation line in a field of view in a lens assembly. The demarcation line varies relative to the orientation of the eyewear to present a visual depiction corresponding to a natural horizon. The eyewear includes at least lens assembly that has an interior cavity defined between an inner lens, an outer lens, and a sidewall defined to join the lenses around the periphery of the lens assembly. A volume of liquid is carried in the interior cavity. The volume if liquid is responsive to changes in the orientation of the eyewear relative to the horizon.