Jonaszówka, also known as Gruby Janek (Fat Johnny), is a unique rock formation located on the right slope of the Prądnik Valley in Ojców National Park, right at the foot of Chełmowa Góra. It forms a rock gate together with another rock formation—Plażówki—though their arrangement is not clearly recognizable due to the wide outlet of the Sąspowska Valley. Jonaszówka reaches a height of about 20 meters and is surrounded by ponds used for farming rainbow trout. Thanks to its location, the rock is a popular viewpoint, offering a picturesque panorama of the Prądnik Valley and nearby attractions, including Ojców Castle. At the top of Jonaszówka, there is a viewing platform secured with railings and equipped with an information board describing the views and providing a panoramic guide. The area is home to rare plants, including Stipa joannis (John’s feather grass). The path leading to the summit is fitted with handrails, making it accessible to tourists. The panorama also features other interesting rock formations, such as Czyżówki, Figowe Skały (Fig Rocks), Ostrogi (Spurs), and Bystra, which attract nature lovers and climbers alike. Jonaszówka is not only a site of natural significance but also cultural value, forming part of the natural heritage of Ojców National Park.