Every 30 seconds or so, "chromatherapy" lights embedded in the side of the Jupiter jetted tub change colour -- blue, green, red, yellow. According to the theory, different lights have different effects on one's mood. It's a bit like being submerged in a psychedelic science-fiction movie.

Controls on the rim of the tub change the speed and intensity of the jets. I cycle through the options, until I find one that gets the water churning like a witch's cauldron. The lights start shimmering like liquid tinsel, and the tub's hidden motor rumbles. Any minute now, even though the tub is in perfect working order, I expect Scotty of the starship Enterprise to yell, "The engine cannae take it, captain -- she's gonna blow!" Hastily, I switch to a less-turbulent setting.

A kind staffer from the Heaven on Earth Spa has placed a clock on the edge of the tub. Apparently, after 20 minutes in this salt-water light show, I'll be cooked and ready to be massaged. At 19 minutes, I accordingly extract myself and toddle over to the towel-padded massage table on the other side of the room. I'm barely conscious by the time my masseuse arrives; minutes after she begins kneading my shoulders, I drift off to sleep.

Heaven on Earth is one of the newest of several spas in Cobourg, a community of 18,000 on Lake Ontario, 300 kilometres southwest of Ottawa. Opened in January, the spa offers a wide variety of indulgences, from a hot stone massage to a chocolate fondue wrap (the latter is a treatment, not a dessert).

Deceptively modest from the street, inside Heaven on Earth Spa is a collection of eight tiled rooms surrounding a cosy "living room" with a fireplace, earth-toned furniture and soothing sage walls. There's also a hardwood-floored yoga studio, where a bearded yogi named Brendan led my friends Brenda and Catherine and me through a private class.

This is the second time my two high school buddies and I have met up for a weekend of facials, pedicures and chocolate. And if you're looking for a fun place to relax with Toronto-based friends, Cobourg fits the bill -- particularly because it allows you to avoid the seventh circle of hell otherwise known as Toronto traffic. You can even take Via Rail right into town, as I did; the spa and its companion property, the King George Inn, are just a 15-minute walk or short cab ride from the station.

But Cobourg has many other advantages besides a convenient location. Founded in 1798, it has retained its small-town Ontario character with many red-brick buildings and tree-shaded streets. Downtown, the massive Victoria Hall -- built in 1860, when the town still looked poised to give Toronto and Montreal a good run for their big city pretensions -- now plays host to concerts and theatre productions.

And for those who find well-traveled places like Niagara-on-the-Lake too precious, Cobourg is a refreshingly real place. Sure, there are gift shops and antiques emporia along King Street, the town's main drag. But you'll also find dollar stores, an IGA and a Home Hardware. For now at least, Cobourg hasn't become too cutesy for its own good.

Perhaps that's because it has a long history as a spa town, so it's not letting the recent boom go to its head.

"This isn't a new yuppie thing," says Phyllis Gosling, innkeeper at the King George Inn. She explains that in the 1800s, Cobourg was renowned for its fresh lakeside breezes, and many wealthy Americans built holiday homes there. Some of these mansions have been turned into B&Bs. But Gosling's inn has an even more exotic history: until five years ago, it was the town jail.

When the province closed the jail, a developer saw the old stone building's potential and bought it. Complicated renovations -- which included covering expanses of un-moveable steel with more esthetically pleasing drywall -- ensued. The warden's house, attached to the jail, now houses seven cozy guest rooms and two restaurants: the Empire Loyalist Pub and Goslings by the Lake.

The former jail has 12 more rooms, including four with "prison showers," operated with a complicated chain system originally designed to keep cons from spending too much time under the water (the showers have since be altered to permit unlimited sudsing). The breakfast room in the "dungeon" is a unique space: most of the old cell bars have been retained, but painted white and decorated with strands of artificial ivy. First thing in the morning, it takes a bit of getting used to.

Gosling and her husband, Peter, took over the inn's management in June 2003. A professional chef, Peter had worked on the Queen Elizabeth 2, at Claridge's in London and the Millcroft Inn in southern Ontario, and the couple had run a restaurant in Brampton for 16 years. So when it came time to revamp the inn's food from casual fare to something a bit more upscale, the Goslings were ready.

Between the pub and the more elegant restaurant, you can now get anything from wings to filet mignon at the King George. Each day, there's also a list of daily specials so long our waitress had to read them off a large sheet of paper. If the sole with coriander and garlic is on the menu, do not miss it.

"We really try to promote that French cuisine doesn't have to be cream sauces," Phyllis explains.

Cobourg is full of surprises like that. In just a weekend, I learned that spas don't have to be ruinously expensive, jails can be cozy and real Main Streets do still exist.

Ottawa writer Laura Byrne Paquet's latest book is The Urge to Splurge: A Social History of Shopping.

If You Go

Getting there: Cobourg is about a 3.5-hour drive from Ottawa. Take Highway 416 south to Highway 401 westbound, then take exit 474 (Division Street) into Cobourg. For information on Via Rail schedules and rates, go to www.viarail.ca or call 1-888-VIA-RAIL.

Spa package: Packages, including accommodations at the King George, some meals and a $100 spa credit at Heaven on Earth, start at $158 per person, double occupancy. Contact the King George Inn, 77 Albert St., Cobourg: www.TheKingGeorgeInn.com or 1-905-373-4610. You can also get a la carte treatments without accommodation by contacting Heaven on Earth, 89 King St. West, Cobourg: www.HeavenOnEarth.ca or 1-866-372-0557.

Other spas: There are dozens of other "wellness options" in Cobourg. You can book day spa services at most Cobourg spas (including Heaven on Earth) without buying an accommodation package. Treatments range from ear candling and reiki to dance therapy and yoga. For details, see www.cobourgwellness.ca