Our return to Hanoi was anticipated along with the rest of the inclusives of our tour. We were dropped in Lau Cai after the ride from Bac Ha and left to our own devices for a few hours. These we used to fill our stomachs with an early evening meal along with a few beers with fellow traveller. Satisfied we returned to collect our bags and whilst I paid one last visit to the conveniences Julian waited outside and fell into a conversation with a gentleman of advancing years, also waiting for his train back to Hanoi. It turned out that the gentleman had been living with his family as a child in Hanoi when the DMZ was formed in 1954. Together, as a family, they relocated to Saigon and initially under French protection remained there throughout the next two decades. They finally left their homeland as some of the 'Vietnamese boat people' in 1978 to eventually settling in Paris, France. He was here as a part of a tour group and must have made a fascinating traveling companion; our conversation with him was riveting enough that when I urged Julian to check his watch we discovered that not only were we three not waiting for the same train, but ours had been due to roll out of the station some 10 minutes prior.
Alighting we followed hundreds of people in single file up stairs into the mouth of Grotte des Merveilles, one of the numerous islands which are hollow. The temperature mercifully dipped as we descended its depths into a massive chamber of stalagmites and stalactites, beautifully lit. We followed the wooden walkway deeper into the womb of the earth to find two more caverns larger than the first, perhaps 200m deep and with a (comparatively) narrow looking exit high up the outer wall. We followed a concrete path, up and down steps, laid to show the very best of the caves features and to protect the fragile and porous rock from millions of feet that pass through here each year. Trapsing in file with about 500 others we 'oooed and ahhhed' at the right places and tutted at those taking short cuts across the rock before exiting and dropping back down many stairs to sea level. We searched for our boat out of the many which were docked in the bay for the same daily purpose and were promptly served a lunch of spring rolls, tofu, fish, veggies and rice whilst our captain set sail for Cat Ba once again.