Read this: Portugal has several summer music festivals, such as Festival Sudoeste in Zambujeira do Mar, Festival de Paredes de Coura in Paredes de Coura, Festival Vilar de Mouros near Caminha, Boom Festival in Idanha-a-Nova Municipality, Optimus Alive!, Sumol Summer Fest in Ericeira, Rock in Rio Lisboa and Super Bock Super Rock in Greater Lisbon. Out of the summer season, Portugal has a large number of festivals, designed more to an urban audience, like Flowfest or Hip Hop Porto. Furthermore, one of the largest international Goa trance festivals takes place in central Portugal every two years, the Boom Festival, that is also the only festival in Portugal to win international awards: European Festival Award 2010 – Green'n'Clean Festival of the Year and the Greener Festival Award Outstanding 2008 and 2010. There is also the student festivals of Queima das Fitas are major events in a number of cities across Portugal. In 2005, Portugal held the MTV Europe Music Awards, in Pavilhão Atlântico, Lisbon.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): What is the Boom Festival?
one of the largest international Goa trance festivals takes place in central Portugal every two years