Trust me, the address is accurate—persist in your search and you'll be handsomely rewarded. Pótkulcs is a hidden bar nestled inside a former light engineering workshop in Budapest's District 6. Once you find the nondescript entrance, proceed through the leefy patio to the adorably gritty, art-laden interior. Attached to the main section is a cavernous performance hall where they host live music concerts almost every evening (with lots of Hungarian folk music). The vibes are laid back and the crowd skews bohemian. During the warmer months, the action shifts to the outdoor patio.
After you leave, it’s worth walking around this mostly working class neighborhood to understand the extent to which Budapest's once grand housing stock was left to decay during communism, and, in areas like this, even after that (whereas in downtown many buildings have recently been refurbished).