La Palma has witnessed half a dozen volcanic eruptions over the last few centuries, and the one in 1949 produced some fascinating terrain for hikers. What follows is a description of a challenging circular hike through some of the most spectacular scenery on La Palma. Along the way, you’ll peer into a gaping crater, tramp over crunchy cinders and ash, and run your camera batteries flat taking artistic shots of lava.
On my way to the San Juan crater
To begin, I drove up to the trailhead at the popular leisure area known as El Pilar. The first part of my hike followed the well-marked forest track leading to Llano de la Mosca, which branches off the LP 301 road a few hundred metres east of El Pilar. This gently undulating section makes an ideal warm up, and is easy underfoot.
From the track, I enjoyed views of geologically-recent cinder cones poking out of the pine forest, their barren slopes tinged in attractive shades ranging from ochre, to coffee browns and slaty greys. Wild flowers added their own vibrant splashes of colour: depending on the time of year, this is an excellent area for several endemic species, including the dazzling Aeonium spathulatum.
It took a leisurely hour or so to reach Llano de la Mosca, and from there I switched to the SL LP 125 path, signposted to Nambroque. The ensuing ascent was more strenuous, but pine trees provided convenient shade most of the time. As I gained altitude, the sporadic calls of Red-billed Choughs gradually turned into a generalized clamour: this species, the symbol-bird of La Palma, roosts and nests on the inaccessible outcrops in this area, and there were lots of raucous choughs flying around on the morning I was there. Nowhere in the UK will you see such large flocks.
The path eventually emerged from the forest to wind its way across pale ash slopes and reach a saddle just below the Nambroque peak. The views were absolutely stunning. To the north, La Palma’s highest mountains were visible, with the Caldera de Taburiente at their feet. Seawards, the massive pyramid of Mount Teide on Tenerife stood out on the horizon, towering well above the layer of clouds. The atmosphere was crystal clear, accentuating all the vivid details of this unique landscape.
The San Juan crater, Hoyo Negro
From the saddle I made a ten-minute detour south to the Hoyo Negro crater. This is actually the crater of the San Juan eruption, and its genesis was an extremely violent affair. Large amounts of ash were blasted skywards from this hole in 1949, while the lava crept placidly downhill from a gash in the volcano’s western flank.
The inner slopes of this somber pit (negro in the Spanish toponym alludes precisely to its dark colour) are made up of layers of fine, sand-like materials pulverized when the volcano exploded. Its contours are far from symmetrical, and its sides are highly unstable. This is no text-book circular crater with a path around its perimeter, but a cataclysmic, awe-inspiring reminder of the forces nature can unleash on occasion.
I sat down on a low stone wall, which had presumably been built to act as a bench for hikers. As is usual on La Palma, at places where walkers stop for refreshment, groups of lizards soon appeared on the scene. They scurried around my feet, quickly grabbing, and fighting over, any crumbs falling from my sandwich. The males are dark grey in colour with a conspicuous turquoise-blue neck patch, the females brown and striped. Somehow they manage to eke out an existence in the wilderness.
Another creature prone to begging food from humans is the Raven. You’ll encounter them at just about all the leisure areas, viewpoints, carparks, and even roadworks on the island: almost anywhere in fact, where people can be found eating outdoors. The relevant authorities are trying to dissuade the public from feeding these wild birds, but it is probably too late to change either the Ravens’, or the public’s habits.
Sure enough, within minutes of my arrival, one of these handsome black corvids suddenly appeared from out of nowhere, and strutted along the ground a few feet away from me, deliberately posing for the camera, or so it seemed. Wildlife photography was never easier!
Despite having inconspicuous flowers, the summit vegetation is also of interest. Some of the plants known locally as crespo (Plantago webbii) can be seen in the background in the above image.
The San Juan lava flow
Having seen the crater of the San Juan eruption, it was time to take a look at its lava flow. I back-tracked for ten minutes to reach the saddle, and then continued along the Volcano Route (GR 131) in a northerly direction. About 45 minutes later, the SL EP 105 path forked left. A steep descent followed to its junction with the PR LP 14.1, where I turned right to reach my objective.
The striated surface, meandering channels, and contorted strands of the San Juan lava impressed with their sheer sculptural virtuosity. Here was natural artwork in stone. The molten rock had issued from a vent in the western flank of the island, and initially followed a gulley downhill. You can get really close and admire the bizarre formations moulded from the viscous material before it hardened.
At the point where the PR LP 14.1 path crosses the flow, the lava had carved a trench through the surrounding materials. This is where I decided to put down my gear, grab my camera, and try to do photographic justice to the subject before me. Closer inspection revealed a host of interesting features, including smooth, gleaming bulges, jagged flanges, chutes, wavy fringes, and entrail-like structures, all cast in the glossy black basalt. Volcanologists no doubt have technical terms for these features, but I’ll go with the old adage of an image being worth a thousand words.
Just downstream of the path I discovered a short section of lava tube, best described as a natural lava bridge.
In the same area I found rectangular patches of crust that were so flat, they recalled slabs of concrete: how on earth had they been formed? As I walked around with my camera, I attempted to interpret the varied topography by trying to envisage the behavior of the lava before it cooled down and lost its plasticity.
Imagine sticky black tar pouring down a rough mountainside. On its way it picks up boulders, spills over ledges, and forms little eddies where the slopes are less steep. Eventually it solidifies. Then, another stream of tar creeps downhill and partially superimposes itself on the previous surface. Fragments of the first layer break off and are pushed forward by the advancing wave. The incandescent goo congeals, and then the process is repeated…
Back in 1949, the raw material responsible for these events was oozing inexorably downwards at a temperature of around 1,000 Celsius. The mind boggles!
To return to my car, and complete my circular route, I headed north to pick up the SL EP 103, and then followed the PR LP 14 gently uphill to El Pilar.
The young volcanic landscapes in the south of La Palma are of exceptional scenic value and, along with the laurel forests and the National Park, are one of the natural highlights of the island that no visitor should miss.