You would be hard-pressed to find a more beautiful site. Set in the valley of the Bannau Brycheiniog, complete with a river and luscious trees, Green Man festival is now in its 24th year. Known for its alternative music, the festival is actually much more than that. Despite its smallish size – just a 25,000 per day capacity – the lineup features not just a truly diverse set of musicians but also literary talks, political debates, a cinema, a wel…