Every one of these is a bookable day out, and most need a ticket sorted before you fly.
Alhambra, Granada: Nasrid palaces from the 13th and 14th centuries stand on a hill above the city beside the Generalife gardens, UNESCO listed since 1984, and daily visitor numbers are capped, so timed tickets for the Nasrid Palaces need booking well ahead.
Sagrada Familia towers: Gaudi's basilica has been under construction since 1882 and remains unfinished, with its tallest spire planned to reach 172.5 m, and timed tickets cover the nave with an upgrade for one of the tower climbs.
Teide cable car: The ride climbs from 2,356 m to 3,555 m in about eight minutes, leaving a short walk to the summit area, and the crater itself at 3,715 m needs a free permit booked ahead from the national park.
Caminito del Rey: This 7.7 km walkway pins itself to the walls of the El Chorro gorge about an hour from Malaga, at points 100 m above the river, and since its March 2015 rebuild it is walked one way with a compulsory helmet.
Timanfaya by coach: Around 51 km2 of lava fields from the 1730-1736 eruptions are toured along the Ruta de los Volcanes because walking is restricted, and demonstrations at the visitor area show ground heat that ignites brush a few metres down.
Mezquita of Cordoba: An 8th-century mosque, begun in 785, had a Renaissance cathedral built inside it in the 16th century, and its forest of striped arches sits on the high-speed line between Madrid and Seville, UNESCO listed since 1984.
Boats from Palma: The harbour handles ferries to Barcelona, Valencia and the other Balearic islands as well as regular cruise calls, and short boat trips run from the resort harbours along the coast.