Event will take place in Priekulu lidlauks. It is located near city of Cesis which is ~89km from the capital of Latvia - Riga.
You can get to Cesis via (public transportation routes and scheduled times can be looked up here :
Latvia, officially the Republic of Latvia (Latvian: Latvijas Republika), is a sovereign state in the Baltic region of Northern Europe and a member of the European Union. Since its independence, Latvia has been referred to as one of the Baltic states. It is bordered by Estonia in the northern region, Lithuania in the southern, to the east is Russia, and Belarus to the southeast, as well as sharing a maritime border with Sweden to the west. Latvia has 1,957,200 inhabitants and a territory of 64,589 km2 (24,938 sq mi). The country has a temperate seasonal climate. (via Wiki)
Latvia is part of Schengen area. If you need a VISA, please check out the information here