How about easing off those New Year aches with a day-long dip in a hot tub? Such an indulgence may seem like a luxury, but, if you happen to be in the right part of the world, there are countless opportunities to bathe for free in one of the many wild, natural hot springs. Some are barely the size of a puddle, others are huge crystal pools, and most are well-kept local secrets. We've rounded up some of the more accessible hot springs you can visit for a truly natural – and completely free – rejuvenating soak.
Travertine and Hot Creek hot springs, USA
You'll find an abundance of wild hot springs is the Californian sierras, and many of them are easy to reach from nearby towns. One of the most popular is the Travertine hot spring near Bridgeport, where you can bathe in relaxing 37C water while enjoying spectacular panoramic views of the surrounding desert. Another, bigger spring is Hot Creek – a very popular pool that is hearted by magma and would be boiling hot were it not mixed with cold water from the creek. Make sure to pay attention to the signs warning you about the sections of the pool that are scalding.
• Travertine Hot Springs, near Bridgeport and Hot Creek, 25 miles south of Lake Mono, California
Saturnia, Italy
Surrounded by thick woods, rolling hills and olive groves, the Saturnia hot springs in southern Tuscany take the form of clear water cascading over rock pools, which you can relax in like your personal hot tub. The water runs at a constant, muscle-soothing 37C and is rich with sulphur, calcium and carbon. The rock pools have been turned white by the minerals, giving them a tranquil glow, and there's absolutely no need to shell out the entrance fee to bathe in the same water at the nearby spa complex. There are several other wild, natural hot springs to dip in around Tuscany – in Petriolo and San Filippo, you'll find even hotter pools, where locals wile away their weekends.
• Terme di Saturnia, 58014 Saturnia, near Manciano, southern Tuscany
Reykjadalur, Iceland
Think Iceland and an image of people drifting dreamily in the Blue Lagoon spa comes to mind. But the country, which sits upon a hotbed of volcanic activity, has no shortage of smaller hot springs and pools you can visit without having to pay an entry fee. Perhaps the easiest for a tourist to get to is Reykjadalur, which translates as Steam Valley. Located a 45-minute drive from Reykjavik, followed by a short hike, the spring is a lush stream surrounded by wild grassland. It's as fresh and invigorating as it comes.
• Around one hour's hike from Hveragerði, in the country's south
Halfway and Lussier hot springs, Canada
In the rich pine forests of British Columbia, there are a great number of hot springs to choose from. In the Nakusp and Arrow Lakes region of British Columbia is an entire area known as the Valley of Hot Springs and there's even a well-trodden hiking route that takes you to some of the most popular ones. While some have now been developed into commercial spa locations, others are still wild and free, such as the Halway hot springs, where the river has been dammed to create a pool where visitors can have a toasty soak in the woodland. Just off the route, in Whiteswan Lake provincial park, you'll find the Lussier Hot Springs, where you can relax in rock pools by the side of the Lussier river.
• Halfway Hot Springs, 25km north of Nakusp
Hot Water Beach, New Zealand
Situated on the coast of New Zealand's North Island, Hot Water Beach is a far cry from the rocky forest springs of Scandinavia. But it offers one thing you'll struggle to find anywhere else: the chance to build your own hot tub in the sand. Naturally heated hot water comes up from beneath the beach, meaning if you dig deep enough you can build your own spa pool. It's become such a popular activity, local cafes will even rent you a spade.
• 12km south of Whitianga on the Coromandel Peninsula, North Island