Summer attractions in Mikołajki involve wide choices of water sports (sailing, fishing, swimming), cycling, horse riding various leisure walks along the lake shore. Further attractions for nature-watchers include sightseeing Masurian Landscape Park with its rich fauna and flora or visiting the settlement of Popielno (situated only a few kilometers from Mikołajki), with the unique stud farm of Polish primitive horses genetically close to the extinct tarpans.
In the Mikolajki Marina visitors may participate in shanty concerts or embark on a pleasure boat going along the trails of Great Masurian Lakes or try a ride on the cable ferry.