The bus goes to Hai 'an by ferry. Haian turns to Beihai. But it's troublesome.

You can go directly to Beihai by boat from Haikou.

Depart every night 18:00. Arrive at the second-class seat of Beihai International Passenger Terminal around 05:00 in the morning: 180(4-person cabin).

Third class: 120 (eight-person cabin). If it helps, thank LZ for adopting it.