Tepealtı is a village in Gerze District, in Sinop Province, Türkiye. Tepealtı lies at 838 m above sea level, in the Küre mountains. It has 105 inhabitants. The nearest city is Sinop, 33 km to the northeast. Among the landmarks around are Carussa (22 km) and Erfelek Dam (16.4 km). Among the natural features are Tatlıca Waterfalls (14.3 km).