The ravine that draws thousands of walkers each year was, for most of its recorded history, a road for nobody but the people who lived in it. Masca sits at roughly 600 metres in the Teno massif, the oldest volcanic formation on Tenerife, dated to around seven million years old. Until 1991 no paved road reached the hamlet. Supplies came up by mule along tracks cut into the barranco walls, and residents descended the gorge to the sea because it was the shortest route out. The geology explains the shape of the walk. Teno's basaltic shield was carved by erosion into a series of steep-sided ravines, and the Barranco de Masca is the most dramatic of them: a defile some 600 metres deep that narrows in places to a corridor barely wider than an outstretched arm before releasing walkers onto a black-sand cove beneath the Los Gigantes cliffs. Palm groves, dragon trees and endemic Canarian flora cling to the terraces. Guanche remains have been recovered from caves in the massif, evidence that the pre-Hispanic population used these ravines long before the Castilian conquest of 1496. What changed the ravine's modern life was volume. By the 2010s the descent had become one of the island's most-walked routes, and erosion, litter and rescue call-outs mounted. The Cabildo de Tenerife closed the barranco in 2018 and reopened it only in 2021 under a regulated permit system, with helmets required, a capacity cap, and access managed from the visitor centre at Masca. That regime is why a masca gorge hike tour today is a booked, counted, supervised affair rather than a spontaneous scramble. The current non-resident adult ticket is 28 EUR, excluding the mandatory transport fee, and entry is confined to Friday, Saturday and Sunday, 07:00–14:00. The restriction has reshaped the valley itself. Masca's terraced houses and the church of the Immaculate Conception remain, but the hamlet now functions as a threshold as much as a destination — the point where the descent begins and where day-trippers on a broader Masca Valley guided hiking tour pause for the view down the ravine. The Teno Rural Park designation, covering more than 8,000 hectares, protects laurel forest, cliff-nesting seabirds and one of the darkest night skies in Europe. The walk's ending is what fixes it in memory. The barranco discharges at Playa de Masca, a cove reachable only on foot or by boat, directly below the 600-metre sea cliffs that Europeans have called Los Gigantes since the eighteenth century. Most operators running masca gorge hike tour tours therefore end with a boat transfer to Los Gigantes marina, which is both a logistical necessity and the only way to see the ravine's mouth from the water. Cetacean traffic in this channel is constant: pilot whales and bottlenose dolphins are resident year-round, a fact that has folded whale-watching into the same coastal circuit. The gorge, once a corridor of necessity, is now one of the Canary Islands' most carefully rationed landscapes.