Visconti of Pisa and Sardinia Ubaldo. In 1207, Lamberto married Elena, the heiress of Barisone II of Gallura, thus securing control over the northeastern corner of Sardinia with his capital at Civita. In 1215, he and Ubaldo established their hegemony over the Giudicato of Cagliari in the south of the island as well. Through advantageous marriages, Lamberto's son, Ubaldo II, secured power in Logudoro for a time. By mid century, Pisan authority was unopposed in Sardinia, thanks to intermarriages between the Visconti family and the other great families of Pisa (Gherardeschi and Capraia) and Sardinia (Lacon and Bas-Serra). Visconti of Pisa and Sardinia The Visconti
Sardinia mainland peninsula. The Strait of Bonifacio is directly north of Sardinia and separates Sardinia from the French island of Corsica. The coasts of Sardinia [ long] are generally high and rocky, with long, relatively straight stretches of coastline, many outstanding headlands, a few wide, deep bays, rias, many inlets and with various smaller islands off the coast. The island has an ancient geoformation and, unlike Sicily and mainland Italy, is not earthquake-prone. Its rocks date in fact from the Palaeozoic Era (up to 500 million years old). Due to long erosion processes, the island's highlands, formed of granite, schist, trachyte,