Sedlo, Prehistoric hillfort in the Šumava foothills near Sušice, Czech Republic

Sedlo is a prehistoric hillfort on the rocky summit of Mount Sedlo at 905 m, the second-highest site of its kind in Czechia after Obří hrad. Its 920 m of ramparts, linking natural rock formations, enclose 2.9 ha in an irregular quadrilateral 440 m long and 32–114 m wide.

Sedlo was built in the 6th–5th century BCE, at the transition from the Hallstatt to the La Tène period, as a refuge with a defensive role. In the later La Tène period it may have housed an elite linked to gold panning on the Otava; Roman-era and early medieval use left only the ruins of older ramparts. Bedřich Dubský excavated here in 1930–1932 and Jiří Břeň in 1953–1955.

The name Sedlo means "saddle" in Czech, referring to the mountain's shape. The site is a protected cultural monument of the Czech Republic. Bronze finds include an arched handle, perhaps a sieve rest, imported from northern Italy.

The summit is reached on the red-marked hiking trail from Albrechtice u Sušice to Žlíbek; the site lies about one kilometre from the village. The path climbs to 905 metres, and a lookout tower stands on the summit. Two springs, in the northwest corner and beyond the northern rampart line, were the original sources of drinking water.

At the foot of the rampart, archaeologists found a stock of pebbles that may have served as sling ammunition. Parts of the burnt rampart suggest the wall was deliberately hardened by fire or destroyed by it.