Sun 27th Oct - Fri 1st Nov - Phong Nha Ke Bang National Park

The overnight SE3 train from Hanoi arrives at Gong Hoi an hour late at 8.50am. I say goodbyes to my two sleeper companions, a couple, both police officers on sabbatical and retirement, and get off the train. I've arranged for a transfer up to the incredibly well-reviewed farm stay and I'm praying that there'll be others on the same train to share the high cost. Fortunately I'm joined by Pete & Rebecca for the half hour drive inland. 

Dong Hoi railway station from the platform.

Three weeks ago a strong typhoon blew through here and every few feet there's a freshly chainsawed fallen tree by the side of the road. Not only that, but just last week the river broke its bank and flooded the valleys in this district. There's dried mud covering leaves and trees up to waist height and higher in many places. If this happened in England we'd be devastated, but they seem to inured to it here.

Phong Nha Farm-stay is run by Ben and Bich, an Aussie/Vietnamese couple who have established a great reputation round here for their tours, and the accommodation from which they're run. The Phong Nha National park was established back in 2003, and got the UNESCO seal two years later. The recent discovery of a couple of very, very big caves within the huge mountainous park area has in the last couple of years drawn the attention of the world's travel media and bucket-listers. It's charted straight in at number three in Lonely Planet's Vietnam must-sees, but since it's slightly tricky to get to has thus far not found its way onto the well-trodden backpacker route. I get the feeling that is about to change though, tourism is poised to hit big here imminently.

My room was had two single beds, each four-postered with lacy mosquito nets, two chairs, two electric fans on the wall, and two more on the floor. The shower block was ten paces away, and the two toilet cubicles annexed to the main building on the other side of the swimming pool. The main house has rooms upstairs, but on the ground floor a large friendly open-plan space with a bar, dining tables, book shelves, a fire pit, notice board and the reception HQ from which the cave and trekking tours are booked.

In the afternoon, myself, Rebecca, Peter and Carmen chose bikes from the farmstay's big collection, and cycled a couple of miles down to Son Trach village from where we could get to Phong Nha cave. Even Pete, an Irish professional cyclist, was forced off his bike by the thick mud left over from the recent flood. Fortunately that passed quickly and we were only waylaid further by buffalo and hoards of young kids all shouting hello, waving, and high-fiveing us as we passed. 

Within seconds of arriving at the village, we met Ben and were introduced to Howard Limbert and his wife Deb. I've been a bit of an armchair speliophile for decades, so was aware of Howard's enormous contribution to caving over the last three decades. My cycling buddies, only later realised why I was acting slightly star-struck, I'd never learnt his name but was well aware of his reputation. To be fair, Deb & Howard work very much as a team, sharing a passion for the final frontier of terrestrial discovery. They now live in the village and have been uncovering the secrets of the vast cave systems here since '92. Their pioneering exploration work is now bearing the fruits of a fast developing Eco-tourism infrastructure here. 

We had a quick chat about caves and beer and Bradford before moving on. All the buildings on the street behind us have been built since the park opened in 2003. Things are changing fast.

We met with a couple of others and between the six of us shared the fixed cost of a boat upriver to the cave. The Son river winds through fields, past settlements and Catholic Churches to a broad hole in a cliff face into which the river disappears.

The village of Son Trach was on the Ho Chi Minh trail, the path used to transport arms and supplies from North to South during the American war. The bridge crossing the river at Son Trach was an obvious target for American bombers disrupting those supplies. Rebuilding it was pointless. The ingenious solution was to use pontoon bridge. Every night it was fixed in position and the trail was open. Before dawn each morning, the pontoons were towed miles up river and hidden in the enormous cave that we were just about to enter. 

It took the US command years to work out how the Viet Cong were managing to keep the trail open at this point, but when they finally did, they sent low-flying jet fighters up the river to attack the cave with rockets. 'Phong Nha' means cave of teeth, named for the stalactites that hung over the entrance, those teeth were broken off by the rockets, leaving jagged scars above the mouth, but they failed to do much damage to the interior, and its use by the VC continued.

Once inside the cave we transferred into smaller punted boat and from the large mouth, went through a narrow oesophageal passage that opened out into successive chambers. These were large enough to store not just the pontoon bridge, but also a field hospital, a school, and a major operations centre among the beautiful and bizarre rock formations. The coloured lighting obviously came a lot later.

The boats took us 1km into the cave before we disembarked and walked back along a raised wooden path that crossed sandbanks and terraces, around enormous limestone stalactites and stalactites.