Kokkola's city centre is small enough to walk. The train station, the market square, and Neristan are all within fifteen minutes' walk of each other. The lakeside and the main cultural venues are similarly close.
Cycling is a practical option for exploring the wider area — Finnish cycling infrastructure is good, and a dedicated path runs from the city centre to the Ohtakari beach area. Bicycles can be rented in town. A car is useful if you want to explore the wider archipelago coast, the Jakobstad area to the north, or the Kruununky nature reserve to the south.
The city bus network covers the main residential areas and the airport, but for a visitor it is rarely necessary beyond getting to or from the station. Taxis are available and reliable; Uber operates in larger Finnish cities but not in Kokkola.