It rises in Garzii Plain, a typical karst plateau, with a length of over 20 km. Downstream of the first spring (Mouth Water) the river crosses a first area of limestone, which forms deep gorges and several small caves.
In the second limestone sector crossed by Garda, it is forming other narrow and deep gorges , receiving small tributaries (Water Stone, Ghiobului Hut) to finally flow in Coiba Mica Cave. Until this point, the valley is called Gardisoara.
The main karst formations in the area are:Coliba Ghiobului Spring, Sura Cave, Apa de la Fata Balacenii Cave, Mouth Water Spring, etc. Downstream of Coiba Mica a stream reappears that is finally lost through Coiba Mare Cave. This cave has the largest entrance in Romania: 47 m high and 74 m wide. Downstream of Coiba Mare, in a small basin, Stone House Hamlet is located, in the neighborhood of which there are some remarkable caves: Vârtop, Vârtop Glacier, Orbului Cave, Oilor Cave, etc. Garda, now known as Garda Seaca, is formed again from a few springs, the most important being Tauz Spring, the deepest siphon in the country: -87 m, through which the streams lost in Coiba Mare reappear. Downstream Tauz, Garda digs its most impressive gorges (Hoancele Caldarilor Gorge, Jilip Gorge, Tauz Gorge) where there are dozens of small caves (- 500 m).