Discover Serra Grossa in Alicante: the underground refinery of La Británica, military bunkers, and the most stunning views of Santa Bárbara Castle. Your practical guide to a hidden gem.
When people talk about hiking in Alicante, they usually suggest the elevator to Santa Bárbara Castle or the beaches. Forget the castle elevator, this is the real adventure. Serra Grossa—the rocky mass on the edge of the city—is often overlooked. Yet, it is this very mountain that hides the most fascinating secrets in the entire area.
It stands only 173 meters tall, but the views stretch all the way to Benidorm. Beneath your feet? A maze of tunnels, bunkers, and oil reservoirs.
Serra Grossa: The Mother of Alicante
They call her la madre de Alicante. This isn’t poetry; it’s pure geology. Half the city was built from this limestone. The City Hall, the theater, the basilica—all of them were literally carved out of this mountain.
Oil Under the Mountain: La Británica Refinery
In 1875, the La Británica oil refinery was established at the foot of the hill. Since there was no space on the surface, they drilled inside. The result was a mind-blowing network of tunnels and cisterns—reportedly over a kilometer of passages. It was the only underground refinery of its kind in Spain, and it’s the main reason I headed out here.
I’m standing near the Sangueta TRAM station (Line 1), looking for the tunnel entrances. They are discreet and overgrown, but if you know what to look for, you’ll find them. I climbed all the way to the main cistern. It’s colossal—like a petrochemical cathedral.
Every gate can be climbed, and every fence has its hole. Quite undignified, I squeezed under a barred gate and got inside. Honestly? There wasn’t much to see in the dark. I climbed the stairs around the perimeter of the cistern to the top and suddenly, up there, I saw a hiking trail and on it—a living woman.
My Two “Greatest” Hiking Strengths
I tried to reach the trail, but the ascent led through steep, overgrown rocks and thorns. I briefly thought about turning back and going around, but then I gave up on common sense and started climbing. On all fours.
If I could be characterized by two “strengths,” they would be these:
- I’m too lazy to turn back and go around anything.
- If I have to choose between a bad path and an even worse one, I’ll definitely pick the worst.
So, there I was, crawling. Sandra (the woman on the trail) must have been highly entertained watching a man with shaking legs conquer that rocky section. But not giving up is in my genes. Ten minutes later, I was standing next to her. “How did you get here through those fences?” I asked, out of breath. “Simple, there’s a beautiful hiking trail leading up from the bottom,” she replied, completely grounding me.
Bunkers and Trenches in Bizarre Sandstone
During the Spanish Civil War, Serra Grossa was a fortress. Because of the port and the CAMPSA fuel reservoirs, Alicante was of huge strategic importance. They built a system of bunkers, guard posts, and trenches here.
Sandra and I split up—I headed along the coast past the bunkers, she went to the other side of the ridge toward the photogenic sandstone cliffs. I found names carved into the rock: from love declarations for Margareta and Julia to Russian scribbles and authentic soldiers’ signatures with pre-war dates.
Did you know? Alicante was the last city where the Republican flag still flew in 1939.
Finally, I reached the westernmost part of the trail with a luxury view of the harbor, the beaches, and Santa Bárbara Castle. But you can always go higher. And that is always my curse. I climbed past wooden railings that might date back to the Civil War, and at the very top, I met my fellow traveler Sandra again.
Something was different; her face was redder than a Paradis pepper. I pulled out my water and handed her my SPF 50 cream. This looked like a serious case of impending sunstroke. We both appreciated that there wasn’t a soul around. After all—tourists.
Campo de los Almendros (Field of Almond Trees)
The mountain has a dark history, too. Near the Alcampo shopping center (where the other side of the trail starts) was Campo de los Almendros—a concentration camp that lasted only six days but left an indelible mark. Fascists held 19,000 people here. They weren’t given food, so the prisoners ate every single almond from the surrounding trees—hence the name. About a thousand people died there in just six days.
Romans and the Bronze Age
It wasn’t until I visited the MARQ museum that I learned Serra Grossa was home to a Bronze Age settlement as far back as 1800 BC. You won’t find much left on-site; the treasures are in the museum. But the realization that people were vacationing here with a sea view 3,800 years ago—for free—is enough to make any modern tourist a bit annoyed.
Just a short distance away, you can find another Roman-era archaeological park—Lucentum.
Anyway, time to find the sea.
The Roman Baths of Albufereta and the “Grumpy” Spaniard
In Albufereta, on the eastern edge of Serra Grossa, you’ll find Roman sea pools known as Puntas. I immediately dipped my feet in. Soaking your blisters where Romans soaked theirs 2,000 years ago has a certain mysticism.
Naturally, I took photos. That is, until an older, “well-traveled” Spanish lady walked into the frame and started screaming at me not to take her picture. “But I’m photographing the Roman pools,” I said. She screamed even louder, claiming that if I wanted to photograph her, I had to pay. She ran over and demanded to see what I had shot.
We scrolled through the camera—first photo, second, third… she wasn’t in any of them. Just the pools. She was stunned. “Why would I want to photograph you specifically?” I asked, delivering the final blow. The look she gave me was a mix of surprise and pure hatred. The fact that she wasn’t in the photo offended her more than the idea that I might have been taking it secretly. No, she did not like me.
Practical Info
- Access: TRAM stations Sangueta (L1) or La Goteta (L2). The trail is marked from there.
- Difficulty: Easy to moderate. Elevation is only 173m, but the terrain is rocky in places.
- Time: 2–3 hours depending on your pace.
- When to go: Autumn and winter are ideal. In summer, there is no shade. Bring water, sunscreen, and a hat. There are no refreshments on the ridge.
- Map: Find it on Wikiloc under “Serra Grossa Alicante.”
- Roman Baths: TRAM station La Isleta.
- Note: Lucentum is closed on Mondays.
