For Gülper See, follow the south-shore outing from the Bockwindmühle at Prietzen to the large observation tower and back. Plan for the tourism route’s 4 km total. It follows meadow paths along the dyke, then woodland paths, with interpretation boards and smaller viewing shelters along the way. You can turn back earlier. A shorter tower approach starts from the parking places on the Gülpe–Prietzen road and follows a woodland path; this is a separate starting option, not the complete nature-trail walk.
The 11.6 km 3-Berge-Tour starts and finishes at the NaturparkZentrum, Stremmestraße 10, Milow. Follow the green horizontal bar on white towards Milower Berg, the orchards, Wolfsmühle and the Bützer/Vieritzer hills, returning through the Stremme valley. The route includes climbs; the Vieritzer summit is an additional detour. Choose this for children already comfortable with a substantial walk. For younger walkers, visit the centre and make a shorter out-and-back towards Milower Berg, turning round while everyone still has energy.
Inside the centre, explore the Havel water model, research table and microscope camera, then try the star-filled experience tent with nighttime animal sounds. These are exhibitions, including preserved specimens, rather than live animal enclosures. Admission is charged. From April to October, regular opening is Friday–Tuesday, 10:00–17:00, with extra opening during Brandenburg school holidays; check the holiday arrangements before travelling.
For a first evening of stargazing, Sportplatz Gülpe at Pareyer Straße 6 has a designated observing area with reclining seats and information. Arrive before dark to find your way around. Alternatively, choose a scheduled observing evening at Sternenblick Parey, Pareyer Dorfstraße 5; check the event arrangements rather than expecting a staffed observatory to open whenever you arrive.