Phong Na caves + Hoi An

The sleeper buses aren't reclining seats. They are lie down spaces that work for short people, but not for tall people. They're designed for Vietnamese passengers.

You've got a good itinerary, but if you decide not to go trekking around Phong Na, then go to Hue instead. You can take a cruise on the Perfume river to see all of the royal mausoleums. And from Hoi An, you can take a daytrip to see the My Son archaeological site.

In Phong Nha, you should hire local guide to travel around the cave to avoid loss the way

does anyone have any recommended guides or companies for the caves?

Check out Oxalis. They are the only licensed tour operator for some of the caves, such as Hang En and Son Doong. Most of their tours are multi-day but they do a 1-day tour to Hang Tien.

do you know if there are also trains to Phong Na? I am guessing the train would take us to Dong Hoi and then we would have to still find our way to Phong Na? Is the bus journey much shorter? I don't mind a longer train ride if it is a sleeper where we can actually get some sleep.

Also, accommodations are available in which nearby town?

In general, I think train transportation is a lot safer in Asia. You can book a soft berth sleeper on the SE1 or SE3 train from Hanoi (both depart in the evening) and arrive in Dong Hoi at 5:35am or 7:25am. I've heard those are quite comfortable and scenic.

From Dong Hoi take a taxi (or bus) to Phong Nha. You may be able to arrange a private transfer via your hotel, also. There are quite a few options for accommodation in Phong Nha but I wouldn't wait to book last minute since many of hotels are in high demand. But this also depends on what style of accommodation you are looking for. We are staying at the Phong Nha Farmstay during our stay, which has received many excellent reviews.

Take the train from Hanoi, no question. Why on earth people take their life in their hands to ride an uncomfortable night bus is beyond me. Book yourself a sleeper on the southbound train and enjoy rather than endure the experience.

where can I buy train tickets? Is it just at the main train station on Le Duan? And how early must I book tickets or can last minute be okay? We will want soft berth, but doesn't have to be first class. Also, are buses to Phong Nha easily accessible from the train station? Are they much cheaper than a taxi? Many thanks!

From my research, it seems that https://www.baolau.com/ is the most reliable site to purchase train tickets as they accept international CCs for a small service fee. If you can wait, you could just purchase them at the train station in Hanoi.

There are 3 ways to get from Dong Hoi to Phong Nha
1) Local bus departs every hour
2) Private transfer (500,000 vnd)
3) Taxi (400-600,000 vnd)