Castro de Sabroso is located on the top of a hill near the right bank of the Ave River, in the municipality of Guimarães, parish of Sande São Lourenço e Balazar. It was an ancient fortified town, inhabited in the second half of the first millennium BC, a period known as the Iron Age, contemporary with the Citania de Briteiros, which is located nearby. Here lived a community dedicated to agriculture and pastoralism, which mastered technologies such as metallurgy and pottery, with an impressive mastery of the extraction and working of granite. The town was abandoned about two thousand years ago, after the Roman control of this territory, when the population occupied the lands of the valley.

The walls of the castro reach, in some sections, five meters high and around four meters thick. On the outside of the walls there is also a remarkable polygonal arrangement, made of well-hewn stones that fit perfectly together. The remains were identified by the Guimarães archaeologist Francisco Martins Sarmento, who carried out archaeological excavations here in 1877 and 1878. The Castro de Sabroso, a National Monument since 1910, is owned by the Municipality of Guimarães, under the care of the Sociedade Martins Sarmento.