“Are we old?”

I immediately check for protruding nostril hairs but, finding none, decide that the girlfriend is probably referring to our sitting in a field in the Brecon Beacons nattering idly about how pretty the sky over there looks and how great it is to go to bed before midnight.

I reply that this conversation will probably form the focal point of my post-festival write-up, and from there launch into a diatribe about gonzo journalism. She looks at me, blinks, then answers her own question “Yes, I suppose we are”.

While we might be getting old, our approach to Green Man 2018 is for us radically new. In the ultimate act of quarter-life rebellion against the Man (not the Green one, obviously) we shun the proscriptive dogma of the festival timetable and march blindly into the arena, following our noses wherever the wind may take us. This adventurous approach offers many advantages to the newly grown-up millennial, chief among them spontaneity and a sensibly middle-aged avoidance of the £8 programme price tag.

We’ve picked the festival deliberately as seemingly the best counterpoint to our frenetic, borderline illegally-polluted London existence; everything about it from the achingly pretty hilltop setting, the on-site yoga, to the accessible Indie/Folk line-up doesn’t so much scream as reassuringly intone relaxation.

One big exception to the easy-listening vibes is Friday’s headliner, the high-octane King Gizzard and the Wizard Lizard. I first came across this psychedelic Australian septet at Glastonbury last year and I thought there was something refreshingly if unnervingly different about them. A year on and seeing them headline an opening night blew me away. They are masters of their craft, and their craft is to stand at the meeting point between order and musical chaos, trusting in each other’s ability, Stu Mackenzie’s occasional marshalling and the awesome eternal power of the trippy backing video to guide them and their audience to alt-rock nirvana. Five minutes in the girlfriend told me she didn’t like them that much; three days later and I just overheard her humming Rattlesnake.

In between headliners we bumble around the various stages spurred by our radical carefree attitude to being anywhere in particular. We stumble on all sorts of hidden gems: Annie McGrath giving an expletive-strewn stand-up set that’s as incongruous with her public school accent as it is unsuitable for eight year olds; the Monster Ceilidh Band brewing up an electro-folky storm in Chai Wallahs; and Rob Deering proving that loop pedals aren’t just for Ed Sheeran and can also be used for entertainment.

I should talk about Fleet Foxes, but given that I listened to their set from the comfort of a cosily furnished street food café round the corner from the main stage I’ll talk about the food instead. The emergent grumpy old man in me wants to rail about the price, but that’s just him not going to many festivals (although as a Londoner the dearth of places accepting card was somewhat unsettling). For Green Man’s size, the array and quality of the food on offer is excellent, and in trendy rejuvenating style vegetarian and vegan eaters are more than adequately catered for (Pie Minister, one of the less healthy outlets, sold out of their three vegetarian and vegan pies before any of their meat options). Particular highlights were the Dosa stand opposite the main stage that drew a shout out from Grizzly Bear and created the world’s first ever onion bhaji too big for me to eat it all, and a ‘Bit of Everything’ from Flavours of Africa.

Grizzly Bear, finishing their European tour promoting their new album, kicked off Sunday evening nicely before handing over to the War on Drugs. The headliners first performed at Green Man ten years ago and Adam Granduciel seems endearingly excited to be back, botching the intro to Strangest Thing after enthusiastically hoofing an inflatable ball back into the crowd. Having seen WoD a few times and as a devoted fan of their recorded work, I’m yet to see a live rendition of Baby Missiles that works for me. Whether it’s unavoidable or deliberate there always seems to be a layer missing, meaning the punchy upbeat riff gets lost in a sea of indistinct chords. In my view, however, this is a vanishingly small price to pay for the power and depth of sound they’re able to pack into their big numbers. Under The Pressure, leading into In Reverse against an exquisite backdrop of rolling Welsh hillside, draws a worthy musical curtain across a thoroughly charming festival.