I would check out the National Parks...I copied some excerpts from the visitor website so you can do some further research on those that look interesting. By the way, that winding road mentioned via a prior post was awesome!!!
"Durmitor National Park
Located at wide mountain region in North West of Montenegro, limited by Rivers Piva and Tara between which there are 23 mountain tops over 2300 meters
Biogradska Gora Unique National Park
Biogradska Gora is located in the central part of Bjelasica mountain massif, between 2 beautiful rivers (Tara and Lim)
In 2009 Montenegro declared this amazing area as a National Park Prokletije. Gorgeous National Park Prokletije is located between Montenegro and Albania
Lovcen National Park
Lovcen is located in rocky region of Dinara Alps. Slopes of Mountain Lovcen steeply, rise from coastal region of Boka Bay and west part of Cetinje
Lake Skadar, the largest in the Balkans, the only national park dominated by aquatic and wetland ecosystems. With 281 species, Skadar Lake represents unique attraction"