Yburg, Medieval castle ruin in Kernen im Remstal, Germany.

Yburg is a castle ruin perched on a hilltop near Kernen im Remstal with surviving gates, vaulted passages, and two cellar chambers on its eastern side. The remains reveal the typical layout of a medieval fortification in this area.

The Yburg was built in the early 14th century by the Truchsessen von Stetten; the exact construction date is unknown. After Schloss Stetten was built in the valley (1384–1387), the castle lost importance. Hans von Yberg sold it in 1443 to the House of Württemberg. Described as dilapidated in 1598, it was repaired in 1659 and given a fourth storey. In 1760/61 Duke Carl Eugen of Württemberg had it demolished down to the outer walls.

The name evolved from Eibenburg through Yberg to Yburg. The Stettener Weinweg, a roughly one-hour loop through the Lindhälder, Brotwasser and Pulvermächer vineyard sites, passes the ruin and explains the grape varieties grown there. The Brotwasser name comes from a court lady at Stetten who secretly dipped her bread in wine instead of water. Since 17 April 2011 sculptures by Karl Ulrich Nuss have stood by the castle.

The ruins are accessible via marked hiking trails that connect to the Stettener Wine Trail with excellent views of surrounding vineyards. The path is clearly marked, making navigation straightforward for all visitors.

The castle had no well of its own, so water had to be carried up from the valley via the Burgsteige path. A plane tree planted in the courtyard in 1845 was removed in 1931 because birds gathering in its crown were eating the surrounding vineyards' grapes.