Set on a sprawling Tennessee farm, Bonnaroo built its identity around multi-day on-site camping and a jam-band-rooted booking philosophy that later broadened considerably.
Barcelona's Primavera Sound built its reputation on a music-critic and indie-focused booking philosophy that later expanded into a genuinely international, multi-city event.
Named after the long-running public television concert series, ACL Festival splits its lineup across two identical weekends in Austin's Zilker Park each October.
Held on the same August bank holiday weekend at two different sites, Reading and Leeds share almost their entire lineup while maintaining distinct local identities built up over decades.
What started as a beachside offshoot of the Winter Music Conference has become one of electronic music's most closely watched annual events, now exported to dozens of countries.
Since its debut in the early 1980s, Rock in Rio has leaned into sheer physical scale — purpose-built festival cities, record attendance figures, and a format now exported to multiple countries.
What began as a touring alternative-rock send-off in the early 1990s is now a permanent Chicago institution with sister festivals on four continents.
Tomorrowland's elaborate main-stage builds and global "Global Journey" travel packages turned a regional dance festival into the closest thing electronic music has to a pilgrimage.
Started on a working dairy farm in the early 1970s, Glastonbury has grown into one of the largest greenfield music festivals on Earth without losing its countercultural roots.
Part concert, part fashion week, part social media spectacle — Coachella's influence on how festivals are built and marketed reaches far beyond its two weekends in the desert.