Among the first Kozjansko Hills lies the lake Slivniško jezero which is also called the Kozjansko sea. The lake is actually a dam on the Voglajna River, with a depth of 14 m and a surface of 86 hectares. After the dam, the Voglajna flows along the foot of Gradišče ( 441 m ) and then through the valley between Gradišče and Prednja gora ( 454 m ). The meandering river almost completely encircles Prednja gora then turns around Rifnik to the Šentjur plain and finally to Store and Celje.
On a shelf on the slope of Rifnik ( 568 m ) are the ruins of a Krško Castle that later came into the possession of the Counts of Cilli. There was an important settlement on top of Rifnik already in the Antiquity. Excellent views are also from Resevnik ( 630 m ), Rifnik’s western neighbor.
Šentjur pri Celju is a local center with a road and rail line leading from Celje to Rogatec.
Rogatec and Podčetrtek
Rogatec was a parish as early as the Middle Ages but it was not granted a market charter until 1875.
In the tributary valley under Boč ( 979 m ) is Lemberg which acquired the status of a market town in 1244 but today it is just a small village and there is no trace of its former economic power. Only a few kilometers away, under Zbelovska Gora, lies the village Sladka gora with its famous pilgrimage church.
The thermal springs of Rogaška Slatina were first mentioned in the 11th century and mineral water has been sold since the 17th century. Well-tended gardens are lined with spa buildings and surrounded by wooded hills.
Between Šmarje pri Jelšah and the Sotla valley stretches a hilly world with several isolated farms, mostly scattered on the ridges. Streams flow into the lake Slivniško jezero and the Sotla.
In the Tinjski Potok valley, under Žusem ( 596 m ) which has great views, is Loka pri Žusmu. On Žusem is a church with two belfries, and on the ridge under the peak ruins of a castle.
There is another castle perched above Podčetrtek which is used to protect the route to the Sotla valley. Nearby is the thermal spa Atomske Toplice. In Olimje near Podčetrtek are the remains of the Minorite monastery with defense towers and an old pharmacy.
The Zasavje Hills end with the Kozjansko Hills.
In the southeast, Kozjansko borders the mountainous slope of Bohor ( 1023 m ), in the east the Sotla valley through which runs the state border with Croatia, and in the north, it borders Rudnica ( 626 m ).
Kozje, the center of Kozjansko sits in the wider part of the Bistrica valley. There are other villages in the valley as well: Lesično, Zagorje, and Planina pri Sevnici. A road to Sevnica runs through these parts. At the foot of Orlica, near Podsreda, the Bistrica brook turns east to the Sotla. Above Podsreda we can still see a Romanesque castle which still looks as it did in the 12th century.
A road from Podsreda leads west via Senovo to Krško and another one east along the Bistrica to the Sotla valley. In the middle of a wide plain lies Bistrica ob Sotli.
The road and the rail line lead up the Sotla via Imena to Podčetrtek and down the Sotla to Bizeljsko and further on to Brežice. Here, the state border with Croatia runs on the Sotla.
From the central courtyard of the Podsreda Castle lead entrances to the museum and gallery rooms and the reconstructed castle kitchen. Especially interesting is the castle jail, hidden under the stairs.
At Olimje near Podčetrtek is a Renaissance castle with round towers. In the 1550 castle, there was a Pauline monastery with its own pharmacy in the 17th and 18th centuries. The pharmacy has been completely restored and the monks will kindly take you to see it. There is another Podsreda Castle ( Podsreški grad ) only 5 km from Podsreda on the north slope of Orlica ( 686 m ). The castle was built in the first half of the 12th century and despite later changes, it managed to preserve its original core almost unchanged. When it was built it was one of the five major feuds of Krško and the seat of the land court. It has been systematically restored since 1983.