This is a list of fortifications in Serbia (Serbian: тврђава, pl. тврђавe, tvrđave). The list includes remains (ruins) of military constructions; castles (Замак), towers (Кула, Кулe) etc.
There are over 30 preserved forts in Serbia, and more than hundreds of sites with remains of old fortifications. Forts in Serbia are preserved from the Roman, Byzantine, medieval Serbian and post-Ottoman eras. The majority of forts have been renovated throughout history with changing rule and adaptations to war technology development. Most of the forts are foundations of modern towns and cities; The Kalemegdan fortress have remains of the ancient city of Singidunum, modern Belgrade. UNESCO World Heritage Site of Serbia, Stari Ras was the seat of the early medieval Principality and Kingdom of Serbia (950–1034, 1113–1276).