Baishamen Park (白沙门公园) occupies the northern tip of Haidian Island, the large river island that sits between Haikou's old city and its newer northern districts. The park has a small lighthouse, sections of planted mangrove along the riverbank, and a beach of sorts on the northern shore. The views back south across the Haidian River toward the city skyline are particularly good in the late afternoon.
The park is popular with families and joggers in the evenings. The mangrove sections attract wading birds, and if you walk the northern shore early in the morning you are likely to have much of it to yourself. Getting here requires crossing one of the bridges onto Haidian Island — it is a short taxi or cycle ride from the old town.