☀️ Gibraltar heat warning — stay safe on the Rock
Summer temperatures regularly exceed 30°C with high humidity. Follow local advice, stay cool and hydrated, carry water (refill free at Casemates Square), avoid the Upper Rock between 12:00–16:00, and use sun protection (hat, sunglasses, SPF 30+). If you feel dizzy or stop sweating, seek shade and fluids immediately.
Full guide: How to cool down in Gibraltar →Key takeaways
- 1.The Great Siege Tunnels are Gibraltar's most impressive military engineering feat — a network of tunnels carved into the Rock by hand during the 1779–1783 siege, housing guns that could fire down onto Spanish lines.
- 2.The History During the Great Siege of Gibraltar (1779–1783), Spain and France tried to recapture Gibraltar from Britain.
- 3.The garrison was cut off by land and sea, under constant bombardment.
The Great Siege Tunnels are Gibraltar's most impressive military engineering feat — a network of tunnels carved into the Rock by hand during the 1779–1783 siege, housing guns that could fire down onto Spanish lines. They're a must-see for history lovers.
The History
During the Great Siege of Gibraltar (1779–1783), Spain and France tried to recapture Gibraltar from Britain. The garrison was cut off by land and sea, under constant bombardment. The British needed gun positions high on the Rock to fire on the Spanish siege lines, but the only way to get guns up there was to tunnel.
Engineer Sergeant-Major Henry Ince began tunnelling with gunpowder blasts and hand tools. The first embrasure opened in 1782, and the guns mounted there proved devastating. The siege was lifted in 1783, and the tunnels — the first of many carved into the Rock — became the foundation of Gibraltar's vast underground military network.
What to See
The tunnels are open to visitors and house a series of exhibits and displays. You'll walk through the original 18th-century tunnels, see the gun embrasures looking out over the isthmus and Spain, and view historical displays, uniforms, and equipment.
Highlights include the original gun positions (some still have vintage artillery pieces), the story of the siege told through panels, and the views from the embrasures — you can see exactly what the gunners saw.
The WWII Tunnels
Don't confuse the Great Siege Tunnels with the WWII Tunnels — a separate, much larger network built during the Second World War. Both are on the Upper Rock; the Great Siege Tunnels are the older, more atmospheric ones. If you have time, see both.
Practical Tips
- Included in the Upper Rock Nature Reserve ticket (£18 adults)
- Open daily 9am–6:15pm
- Allow 30–45 minutes
- Wear flat shoes — the tunnels are uneven and dimly lit
- Cool inside (18°C) — bring a layer
- Not wheelchair accessible — narrow, uneven floors
- Accessible by cable car, taxi, or on foot from the top station
The Great Siege Tunnels are a powerful piece of military history — hand-carved under fire, they saved Gibraltar and defined the siege. Combine them with the WWII Tunnels, St Michael's Cave, and the macaques for a full Upper Rock day.
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Daniel Toledo
FounderGibraltar-based writer and founder of Gibraltar Unlocked. Covering local food, travel, history and life on the Rock since 2023. Also builds web apps at instatales.ai.
