South Island ▷ Southland ▷
Southland is one of those places where staying in a holiday park actually makes sense as a strategy, not just a budget call. The region is raw, windy, and spread out, so having a solid base with hot showers and a kitchen after a long day on the Southern Scenic Route or deep in The Catlins is genuinely appreciated. My pick for full-facility camping around Invercargill is the Invercargill Holiday Park - it's got everything you need and is well set up for campervans.
Out in the Catlins, the Catlins Newhaven Holiday Park run by Grant and Deborah is a goodie - friendly, well-run, and a decent base for tackling the detours. The campground at Curio Bay has an absolutely cracking location right near the Hector's Dolphins habitat, though the facilities can be hit and miss. Worth it if you're spending a night or two there, since dusk is prime dolphin time. There's also decent freedom camping nearby if the holiday park doesn't suit.
Further west along the coast, the wind can absolutely batter the exposed coastal spots. If it's howling at Monkey Island or similar, the Orepuki Tavern is a smart backup - you pay for a site and get the equivalent back in drinks, which is pretty classic southern hospitality.
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