Boston Calling is a brand-new music festival that will hold its first installment in Boston’s City Hall Plaza 5/25-26, and it’s got a lineup that leans heavily toward accessible, middle-of-the-road indie and alt-rock. The National will co-headline alongside the suddenly omnipresent Fun., and the lineup also features the Shins, Dirty Projectors, the Walkmen, Andrew Bird, Matt & Kim, Ra Ra Riot, Cults, and Youth Lagoon, as well as stuff like the popular-as-fuck Icelandic folk-pop crew Of Monsters & Men. Check here for all the details.