I have indeed. We were there the last weekend of July in 2008. Unfortunately, that was pre-opening weekend, which was just OK. The big opening party was the following week.
From some notes I wrote after the trip:
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This year's 18th edition, as it was for the past couple of years, is being held on a beach in the village of Popovka. Popa means butt in Russian. Popka is the diminutive form of the word. You can get where I'm going with this, and thus understand what I though about this little village. To say it was somewhat undeveloped would be an understatement.
Even so, each summer, thousands of people descend on this little town to help enrich its inhabitants by eating at its handful of cafes, relaxing on its beaches, frequenting its tiny stores, and renting every room that passes for a hotel, hostel or bedsit. Our “elite hotel†was one of maybe 2 finished houses in what appeared to be a small planned neighborhood of decent sized houses. One of our hostesses explained that the other homes were unfinished due to Ukraine's political and economic instability.
The Republic of Kazantip itself was still under construction when we arrived. Friday night it wasn't even open yet so we checked out the nightlife the neighboring town of Mirny ("peaceful"... not quite true as we had a bit of tension with some guys whose women were more interested in us). That “nightlife†was a couple of cafes and one small nightclub, which I dare say we helped bring to life. It was… an experience.
Saturday, we stood in line to purchase our Kazantip passes and went inside to take a look. We'd seen videos online of daytime parties and people dancing on the beach and in the water, but given our early arrival those scenes were nowhere in sight. Instead, it was a chilled afternoon on the beach for us and the other early birds. [although the set-up looked identical to what you see online]
We returned later in the evening and the event slowly got underway. Only three of the music zones were open and a large section of the site, known as “Marsâ€, was not yet completed. Still, it was an entertaining night moving from bar to bar and dancefloor to dancefloor. We were most impressed by the DJs at the Inside zone, and by their promoters' inventive bumper stickers all around town.
One notable thing about our stay was that the people we ran across were all very friendly. We stuck out a bit in the crowd (2 Americans, an Israeli, an Australian, a Swede and an Indian!) and people approached us from all over Russia and Ukraine – I met people from Donetsk to Syktyvkar.
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I'd like to go back someday when Kazantip is in full swing to see what this festival is really like. I hear good things. They also get some pretty big international and Russian DJs down there over the course of the month. Check their site for listings and plan accordingly.