The Thracian Valley boasts tremendous wine making potential because of the rich diversity of microclimates that the region offers. It's a big region with a long history of wine production.
Most of the wines from this region are labeled as Thracian Valley PGI, although there are quite a few wineries releasing good quality wines as table wine. Officially at least, the Thracian Valley has a number of official appellations but based on my recent visits I can find very few producers who are genuinely interested in using them.
The romantic old town of Plovdiv acts as the centre of the region. In the surrounding countryside there are a number of appellations to explore but few producers
To the North West of Plovdiv, Nova Zagora is one such appellation and the area has become home to interesting sparkling wines produced by Eduardo Miroglio, an Italian who was early into the potential of this area.
The most interesting grape variety for me is the the red Mavrud but there are a number of other local varieties that demonstrate potential. Melnik and Gamza in particular are popular while there is also mild producer interest in obscure grapes such as Rubin, a robust type and Bouquet which can be made in a young fruity nouveau style. There are also minor grape varieties such as Pamid that were once popular but now only small amounts survive.