Put safety updates first
Rain and wind can affect boat routes. Do not assume a trip will run to its original schedule; check updates from the port, ticket provider, and operator. The Bay Management Board publishes route and visitor information, but same-day status should be confirmed through current operating channels.
A city alternative
Quảng Ninh Museum presents geology, the sea, history, coal mining, and culture. It can be an indoor option when outdoor activities are postponed, but check opening hours and current exhibits before going. A day with a changed plan can still help you understand the place you are visiting.