Besides olive groves, southern Híos’s gently rolling countryside is home to the mastic bush, and the twenty or so mastihohoriá, or mastic villages. Since the decline of the mastic trade, the mastihohoriá live mainly off their tangerines, apricots and olives, though the villages, the only settlements on Híos spared by the Ottomans in 1822, retain their architectural uniqueness, designed by the Genoese but with a distinctly Middle Eastern feel. The basic plan involves a rectangular warren of tall houses, with the outer row doubling as perimeter fortification, and breached by a limited number of gateways. More recent additions, whether in traditional architectural style or not, straggle outside the original defences. Of the surviving villages, three stand out: Pyrgí, Olýmbi and Mestá.