Jurassic invertebrate fossil sites in the so-called Sierra de Arcos (NE Iberian Chain), between the localities of Oliete and Andorra (Teruel province) are historically known by their fossiliferous wealth as well as by their accesibility and superb oucrop conditions. They are located within the Cultural Park of River Martin, being one of the current prominent scentific values of this protected area. They have also been the reference point for many classical palaeontological (Systematic, biostratigraphic, palaeoecologic) monographs and stand as the type-locality for some ammonite and bivalve taxa. Main risks affecting these outcrops are the destruction and uncontrolled fossil collecting. Protective measures would involve the efficient management of the park, and intense and long work of social awareness