The rain's getting heavier, and the light is starting to close in.
Option One: head for shelter, and hide away from the elements.
Option Two: take all your clothes off, and ease into a hot bath at the foot of a steep hill, overlooking a roaring gorge swollen by the rain.
When you're at the ecoYoga centre in Argyll, it's axiomatic that you'll choose Option Two. Not out of any sense of overt exhibitionism, but just … because.
Because in all senses of the phrase, this place is off the grid: remote, tranquil, and espousing all aspects of the sustainable, at-one-with-nature lifestyle.
So it's perfectly natural to have a lovely relaxing hot bath while raindrops keep falling on your head, and you soak up the uninterrupted views of the magnificent landscape all around.
True adherents of the Scandinavian hot/cold, pleasure/pain principle normally alternate the bath with a dip in the chilly gorge, but it's moving too quickly today. That can wait for tomorrow …
So where is this nirvana, and why does its name feature the word yoga so prominently?
We'll address the second question later, but first it's important to give a sense of place: ecoYoga is at Inverliever Lodge, not far from Kilmartin in Argyll.
For decades, it was used by a charity as an out-of-town retreat for underprivileged city youngsters, until funds ran out.
Current owners Nick and Rachel Loening had the inspired idea to take it over in 2005 and transform it into a destination that combines two of their passions: yoga and green energy.
It's a two-and-a-half-hour drive from Glasgow, although for a small supplement there's a minibus pick-up from city-centre stations or the airport (more relaxing, and more sustainable).
The centre is powered entirely by its own hydro-electricity system, which also generates a surplus for the grid.
In practical terms, that means two things: Nick loves it when it rains (and being Argyll, it frequently does); and guests have an endless supply of hot water.
Hence the lower gorge bath, one of two outdoors - the other's less spectacular, and more for a quick dip when you've grown accustomed to the concept of bathing al fresco.
There's also a large hot tub, covered by a glass dome, with a cold plunge barrel outside. Oh, and massage sessions and an underground sauna, reached by a secret stairway. Really: who said green living couldn't be fun too?
All food (included in the price) is prepared in the communal lounge/dining room/kitchen.
It's strictly vegetarian, which initially daunted this omni/carnivore, but never have I tasted such flavoursome meals, blending recipes from across the globe with ingredients grown on site. All hail wonderchef Claudia Escobar.
Her approach even inspired a rare detour for me from standard instant/filter coffee into the world of herbal teas, served DIY in the nearby workshop cafe around a wood-burning stove, where you can chat with other guests, dream, or just nap.
Yes, sleep's a really strong selling-point. The individual bedroom cabins are comfortable, if furnished basically, but the investment has wisely gone on the super-luxury mattresses. One morning, after a good eight hours, I managed to have breakfast, then return for a quick snooze that lasted three hours.
No shortage, then, of things to do here (slowly, gently, you understand). More vigorous choices abound: walking, cycling, sailing on Loch Awe or off the Argyll coast. Another time, if the energy can be summoned.
Or (and you're right, I've been putting off mentioning it) yoga. Lots of yoga.
Clearly, it would have been disingenuous to visit somewhere called ecoYoga and not try, for the first time in my life, to contort my body into all sorts of alien shapes.
Nick and Rachel bring various yoga masters to the centre as part of their retreats, using a purpose-built studio with under-floor heating. Nick himself, who introduced ashtanga yoga to Scotland when he was based in Edinburgh, also teaches.
But for our visit, guidance was by Gingi Lee from London, a recognised guru. He took this novice and showed me that basic yoga was neither weird nor particularly difficult, even if dedication and practice clearly help. (It certainly had for other guests, forming incredible figures around us.)
But then an ageing back rebelled, and it was deemed unwise to continue. Relieved? Partly, but also a tad disappointed, given how easy it is at ecoYoga to embrace things my conservative, suburban, middle-aged self might otherwise shun.
And there was, of course, an obvious solution to the back pain. Lead me back to that hot bath …
Calum MacDonald was a guest of ecoYoga Centre, Inverliever Lodge, Ford, Argyll
Retreats start at £425 for three days, all meals included.