Festival-goers in Budapest, Hungary, who were daring enough to use one of the portable toilets at Sziget Festival were rewarded for their bravery when they discovered one of the loos led to a secret party.A clip shared to Facebook by Dutch native Fabian Ruivenkamp shows surprised music fans opening a portaloo door, before being led down a narrow corridor and into another venue full of raving dancers.According to Ruivenkamp, the rave is kept secret from the majority of festival attendees. The clip had earned 1,800 views on Facebook at the time of writing. Credit: Fabian Ruivenkamp via Storyful