For a country you can cross before your coffee goes cold, Lebanon contains enough surviving historical sites to fill a continent.

The Temple of Bacchus at Baalbek still stands in all its impossible scale, rising out of the Bekaa Valley as if the Romans are about to return.

Down on the coast, the Crusader castle at Byblos watches out over the Mediterranean from one of the oldest continuously inhabited cities on Earth.

Farther to the south, there is a functioning monastery that’s welcomed pilgrims since Jesus walked the coast of Tyre, and in the mountains above, the Qadisha Valley shelters hermitages carved into the cliffs.

Antiquity is the ambience here.

I didn’t have time to visit them all while I was in Lebanon to attend a wedding, but I did visit Jeita Grotto, a vast Jurassic-era cave network that’s open to the public that sits a mere 11 miles north of Beirut.

Visiting Jeita Grotto from Beirut

Our host at Damask Rose Guesthouse, where I'm staying, isn’t available this morning to be our driver, although he’s absolutely keen to take me to see anything we might like when he is available.

Instead, he has found someone who works at the nearby garage to take us.

He either doesn’t speak English or simply can’t be bothered to have a broken conversation with us. I don’t blame him for either.

From the largely Maronite Christian suburb Zouk Mosebeh where the guesthouse sits, it’s barely a 10-minute drive to Jeita Grotto.

The lanes and the peeling shops give immediately onto the deep valley of the Nahr al-Kalb river.

In the summer month of June, it’s bursting with pink bougainvillea and spiky herb bushes.

Concrete blocks line the outside of the precipitous switchbacks, and before I've warmed up my seat, I arrive.

Buying tickets

You don't need to book a guided tour in advance to visit Jeita Grotto, but they are available.

I stroll across the car park where my driver dropped me off, buy a ticket from the kiosk in US dollars—for around $10, if memory serves—and wait to be taken up to the cave entrance.

A cute land train brings visitors up to the entrance. I don’t see any real need for it, but it’s a nice touch and ensures that visitors arrive in reliable groups.

While I wait for it to come around, an affable Aussie tourist strikes up conversation.

I’m wearing a Barmah Hat, so he mistakes me for a fellow countryman. He’s not bothered when I break the news that I’m English and seems delighted to have met me. He gives me a “rock-on” gesture and a huge grin before heading off with his girl.

Walking through the upper gallery

Jeita Grotto is formed of two galleries: upper and lower cave networks that are connected but accessed separately.

The tour starts at the upper gallery.

Partly to protect the ancient calcite formations from dropped phones, and partly to maintain a reverent, cathedral‑like atmosphere, phones are not allowed inside the caves.

So I dutifully place mine in a locker and head in, slightly dismayed that I won't be able to take photos to share.

The size of the chambers within the cave is stupendous.

It feels like stumbling into the lair of some ancient, banished beast, such as Grendel or Typhon.

The lighting hints at infinite hidden passages, and beneath the suspended gangways lies a true abyss.

From somewhere far off comes the sound of rushing water.

Signs instruct visitors to keep noise to a minimum, but they’re entirely superfluous.

Everyone is speechless under the spell of uncovered beauty, and remained so.

This cave supposedly houses the largest known stalactite—a fact that I can’t verify but find easy enough to believe.

They hang like daggers from the vaulted ceilings, and some must be well over four metres long.

Lying undisturbed for so long, many stalactites have met their partner stalagmites, rising up to touch fingers.

A few must have achieved connection very long ago because the resulting columns have grown outwards to resemble the bastions of some wet and glistening subterranean fortress.

And so one chamber opens onto another through narrow holes in the rock.

One chamber is as wide as a church; another forces the walkway to twist around rocky hummocks and porcupine outcrops of stalagmites.

A few formations look so delicate they seem to vibrate at the mere prospect of a loud noise.

The history of Jeita Grotto

I needn’t have feared who or what the caves are home to.

When I reach the end of the walkway in the upper gallery, the only beast waiting for me is a young teenager whose father lectures in the Lebanese University’s Department of Archaeology.

He breaks the spell and starts reeling off facts with the confidence of someone raised on field trips.

The lower gallery was discovered in 1836 by an American missionary called William Thomson, the son of a Presbyterian minister.

Engineers from the Beirut Water Company penetrated a kilometre into the cave by 1874.

And since the mid-twentieth century, spelunkers and speleologists (cave scientists) have revealed a cave network that runs for almost 9 kilometres.

Beneath the caves runs the Jeita Spring, a vast karst aquifer that supplies roughly three‑quarters of Beirut’s drinking water.

Shortly after the lower galleries were opened to the public in 1958, the dry upper galleries where I’m standing were discovered.

Despite its enormous scale, visitors are only allowed so deep into the cave.

There’s a persistent myth that deeper access is restricted because of low oxygen levels, but the caves aren’t sealed, and natural fissures keep them well ventilated.

For his enthusiasm and knowledge, the young man earns the tip I leave him before I head out to explore the lower galleries.

The boat ride through the lower caves

Housing the aquifer mentioned earlier, the only way visitors can enjoy the lower part of the cave network is by boat.

We climb in, and our guide pushed me off under an arched ceiling low enough that everyone in the boat instinctively ducks.

On the other side is a vast underground lake, electric blue under the mood lighting.

Our boat drifts this way and that, just long enough for us to begin absorbing this staggering display of nature’s grandeur that was hidden for millennia.

Emerging from the cool of the caves back into the warm afternoon sun about two hours after I arrived, all I can think is that beauty this spectacular has no business being so close to the capital—and that this must be the most impressive cave system you can visit without flying to South America.