GUIPUZCOA, a maritime Basque province of northern Spain bounded north by the bay of Biscay, west by the province of Vizcaya (Biscay), south and south-east by Alava and Navarre and north-east by the river Bidassoa, here the frontier of France. The area is 728 sq.m., estimated population (Dec. 31, 193o) or 488 per sq.m. Situated on the northern side of the Cantabrian mountains at their junction with the Pyrenees the province has a deeply dissected and highly picturesque surface with a much indented coastline and numerous harbours none of which are of the first importance, the chief are San Sebastian, Pasajes, Guetaria, Deva and Fuenterrabia. The rivers, Deva, Urola, Oria, Urumea, Bidassoa are all short, rapid and unnavig able. The climate is mild and moist and the soil is mostly rather infertile clay in the valleys ; in spite of this cultivation is careful, but the province has to import grain. Gorse and heath occur on the windswept areas and there are forests of oak, chestnut, pine, with a good deal of holly and arbutus. Apple orchards are nu merous and much cider is made. The province is rich in minerals such as iron, lignite, lead, copper, zinc and cement, zinc being important. Fisheries are important; cod, tunny, sardines and oysters being procured. There are ferruginous and sulphurous springs in many places, and these and the mild climate attract summer visitors. The province is concerned with international trade via the French frontier and its custom house on the Bidas soa is the most important in Spain, but it is chiefly remarkable for its development of local industries. Cotton and linen stuffs are made at Irun, Renteria, Villabona, Vergara and Azpeitia, baskets at Zumarraga, arms and gold work at Eibar, Plasencia and El goibar, chemicals at San Sebastian, Onati and Irun. Paper and timber-work are developed at San Sebastian, Irun, Onati and To losa. The Pasajes district is famed for its wines and liqueurs and large numbers are employed in this industry. The main railway line from Madrid northward to the French frontier runs through the province and it has loops to most of the important industrial centres. In consonance with the development of industries, roads are numerous and on the whole good in this province which, after Madrid, Barcelona and Vizcaya, is the most densely peopled in Spain. On the steep Cantabrian slopes roads are difficult and in rural areas there the ox cart is still widely used. The capital is San Sebastian, a port with a population of 78,432. The other towns named are mostly comparatively small. A good deal of emigration takes place from the province but, as in other indus trialized areas the birth rate keeps high, and there is also con siderable immigration from other parts of Spain, but the general Basque character of the population maintains itself fairly well and the province is relatively prosperous industrially and related in many ways to its western neighbour Vizcaya.