Carboniferous carbonate platforms are known to develop high-relief, flat top and steep microbial-boundstone slopes. Prominent examples were reported from the Bashkirian–Moscovian of northern Spain and are commonly used as analogues for contemporaneous hydrocarbon reservoirs, e.g., in Kazakhstan and the Pricaspian Basin (Tengiz, Karachaganak, Kashagan and Astrakhan fields). Here we report on the isolated Valdorria carbonate platform, formerly equally named Valdeteja platform, located in the southern part of the Cantabrian Mountains, in northern Spain. The outcrop shows a 14 km-wide complete sequence, from platform nucleation to demise, and entirely exposes a flat top, a high relief slope and primarily horizontal basin deposits. Laterally and vertically traceable stratal patterns exhibit three phases of growth, each delimited by a major discontinuity surface presenting dissolution, karsts and/or calcretes features.