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<div>The polymetamorphic basement of the Tisza Unit forms a detached</div><div>fragment of the Variscan European foreland of the Neotethyan</div><div>realm. A clockwise evolution path of a gneiss-amphibolite complex</div><div>of the Tisza Unit was reconstructed, investigating the polymetamorphic</div><div>rocks of the borehole Baksa-2, SE Transdanubia, Hungary.</div><div>The results obtained by microstructural and mineral paragenetic</div><div>observations, mineral chemical analyses, and thermobarometric calculations define a P-T loop which suggests a complex Variscan</div><div>polyphase model rather than a pre-Variscan - Variscan polycyclic</div><div>one. The early part of the prograde path with kyanite is characterized</div><div>by T-P conditions of 480±50¡C and 470±70 MPa, respectively. The</div><div>metamorphism reached its peak at 660±25 ¡C and 750±50 MPa,</div><div>when both kyanite and staurolite were stable. This metamorphic climax</div><div>was followed by a nearly isothermal decompression to 440±2 0</div><div>MPa at 650±40¡C. This event is marked by the presence of sillimanite</div><div>and a second generation of garnet, and is closely related to the collisional Variscan granitoid magmatism observed in considerable parts</div><div>of the Tisza Unit. In amphibolites intercalated with gneisses, only this</div><div>last event was preserved, providing T-P estimates of ca. 650-690¡C /</div><div>400-500 MPa. The present paper provides the first demonstration of a</div><div>continuous, clockwise P-T path from the metamorphic basement of</div><div>the Hungarian part of the Tisza Unit.</div>