Spain is a transcontinental country located in southwestern Europe and northern Africa, occupying about 84.6% of the Iberian Peninsula. Its territory includes a small exclave inside France called Llívia, the Balearic Islands in the Mediterranean Sea, the Canary Islands in the Atlantic Ocean, and several territories on or near the North African coast, including the autonomous cities of Ceuta and Melilla and the plazas de soberanía (Islas Chafarinas, Islas de Alhucemas, Isla Perejil, and Peñón de Vélez de la Gomera).

The Spanish mainland is bordered to the south and east almost entirely by the Mediterranean Sea (except for the small British territory of Gibraltar); to the north by France, Andorra, and the Bay of Biscay; and to the west by the Atlantic Ocean and Portugal. With a land area of 504,782 square kilometres (194,897 mi²) in the Iberian Peninsula, Spain is the largest country in Southern Europe, the second largest country in Western Europe (behind France), and the fourth largest country in the European continent (behind Russia, Ukraine, and France). It has an average altitude of 650 m.

Its total area including Spanish island territories is 505,370 km² (195,124 sq mi) of which 499,542 km² (192,874 sq mi) is land and 5,240 km² (2,023 sq mi) is water. It has the 30th largest Exclusive Economic Zone of 1,039,233 km² (401,250 mi²). Spain lies between latitudes 27° and 44° N, and longitudes 19° W and 5° E. Its Atlantic coast is 710 km (441 mi) long. The Pyrenees mountain range extends 435 km (270 mi) from the Mediterranean to the Bay of Biscay. In the extreme south of Spain's mainland lie the Straits of Gibraltar, which separate the Iberian Peninsula and the rest of Europe from Ceuta and Morocco in North Africa.

Most of Spain's boundaries are water: the Mediterranean Sea along the east from the French border down to Gibraltar and the Strait of Gibraltar, and the Atlantic Ocean on the northwest and southwest (in the south as the Gulf of Cádiz and in the north as the Bay of Biscay). The Spanish autonomous cities of Ceuta and Melilla are Spanish enclaves lying in mainland Africa in territory claimed by Morocco and are located on the coast of the Alboran Sea, with Ceuta at the very mouth of the Strait of Gibraltar, and Melilla closer to the border with Algeria. The Canary Islands, geographically and geologically part of the African continent, are located in the Atlantic Ocean.

Spain also shares land boundaries with France and Andorra along the Pyrenees in the northeast, with Portugal on the west, with the small British colonial Territory of Gibraltar near the southernmost tip, and with Morocco in its autonomous cities of Ceuta and Melilla, and certain other small but uninhabited enclaves, mostly capes and small isles.^{[citation needed]} The affiliation of Gibraltar has continued to be a contentious issue between Spain and Britain, and the sovereignty of Spain's enclaves, or plazas de soberanía, on the Mediterranean coast of Morocco is disputed by Madrid.^{[citation needed]}

Spain also has a small exclave inside France called Llívia, which is a mountain village in the historical comarca of La Cerdanya, forming part of the historical territories of Catalonia.

Most of Spain's peninsular region consists of the Meseta Central, a highland plateau rimmed and dissected by mountain ranges. Other landforms include narrow coastal plains and some lowland river valleys, the most prominent of which is the Andalusian Plain in the southwest. The country can be divided into ten natural regions or subregions: the dominant Meseta Central, the Cantabrian Mountains (Cordillera Cantabrica) and the northwest region, the Ibérico region, the Pyrenees, the Penibético region in the southeast, the Andalusian Plain, the Ebro Basin, the coastal plains, the Balearic Islands, and the Canary Islands. These are commonly grouped into four types: the Meseta Central and associated mountains, other mountainous regions, lowland regions, and islands.

The Meseta Central ("Inner Plateau") is a vast plateau in the heart of peninsular Spain, which has elevations that range from 610 to 760 m. Rimmed by mountains, the Meseta Central slopes gently to the west and to the series of rivers that form some of the border with Portugal. The Sistema Central, described as the "dorsal spine" of the Meseta Central, divides the Meseta into northern and southern subregions, the former higher in elevation and smaller in area than the latter. The Sistema Central rims the capital city of Madrid with peaks that rise to over 2,400 m within the Madrid region. South-west of Madrid, the Sistema Central shows its highest peak, Pico Almanzor, of almost 2,600 m. The mountains of the Sistema Central, which continue westward into Portugal, display some glacial features; the highest of the peaks are snow-capped for most of the year. Despite their height, however, the mountain system does not create a major barrier between the northern and the southern portions of the Meseta Central because several passes permit road and railroad transportation to the northwest and the northeast.