Cat Ba is known for its seafood, and several large places to eat lie along the harbour road and Nui Nuoc with tanks full of live seafood and bowls of shellfish. Your best bet is forget about the menu and point at what you want, although you could end up with a hefty bill at the end of it as prices are worked out on a per kilo basis.
If you're not bothered about seeing your dinner swimming around in a tank before it ends up on your plate, the options are endless: every building is either a hotel, restaurant or, more likely, both. Menus are similar though, offering mostly Vietnamese dishes with an occasional Western option. The Good Bar -- underneath Noble House -- has a wide range of Western dishes, as does the more upmarket Green Mango, which is highly recommended, particularly if you want a decent glass of wine or a cocktail. Most of these places are open for breakfast.
For dining with a difference, head out to one of the floating restaurants on the harbour. Call the numbers displayed on the signs for a pick up.
If you have a sweet tooth you'll be excited by the ice creamery opposite the pier, but we were disappointed with our "fresh" ice cream -- more sugar than cream. Over the road, overlooking the harbour, a number of drink places open up at night serving -- among other things -- sugar cane juice.
For a drink, The Flightless Bird, on the western stretch of the harbour road, has always been a decent choice, but A Good Bar, by the junction with Nui Nuoc west, was where it was at on our last visit: LaRue is 20,000 VND a glass.