Well, some people mention Kalibiru as a National Park, while it is not. Kalibiru is a rural tourism destination managed by local people. Kalibiru indeed has a potential. It is located at the lines of lush green Menoreh Hills.
Kalibiru is located 450 m asl, about 40 km from Yogyakarta city which can be reached by about 60 minutes drive. The road to Kalibiru is narrow due to its location in rural area. But along the drive you will pass interesting view, of farms, village, and mountains. Kalibiru is designed for small scale tourism that some bigger group on coach will not be possible, except if they use local 4WD.
From the peak you can see Menoreh hills with water reservoir. There are 3 view points where visitors can be photoed with the beautiful dramatic (some say instagramable) panorama. And as Kalibiru is getting more popular, now, weekend is usually crowded. That climbing to the view point has long queue. It is better to visit on weekdays. Visitors will be tied using rope for safety and local photographer will take some pictures and visitors can have copy by paying some amount of money. If you plan to climb to the view point, do not forget to wear pants or trousers.
There are some food stalls located near the parking area. They have local menus, from gudeg, chicken, and rice.