Do you know where your recycling goes?

One day each week, people across the region trudge to the curb carrying big plastic bins full of empty milk jugs, dented dog food cans, glass bottles, and newspapers.

Later that day, trash collectors empty the box es into a recycling truck, which rumbles away, out of sight and out of mind.

But where does all that recyclable trash go? Is it really recycled -- old milk jugs into new -- or does it, in the end, somehow get dumped along with the rest of the trash in some unknown landfill?

Following one family's recyling box contents along this trail reveals that, yes, what's put in your recycle bin really does have a second life down the road.

It is made possible by a network of Willy Wonka- style "smart" machines that can be found across the suburban landscape but that most consumers never see. Using a combination of super-magnets, air blasts, high-tech photography, and decidedly low-tech crunchers, these gigantic sorters reduce mountains of our daily garbage into neatly grouped raw materials that end up as, say, a soda bottle in China or a car part in Canada.

There is an increasing amount of recycled trash to feed the process. Between 1990 and 2004 , the amount of municipal solid waste recycled in Massachusetts more than tripled -- from 10 percent to 35 percent , according to the state Department of Environmental Protection.

The trail of one family's recycling starts on a recent Thursday on Hinckley Road in Milton , where four full recycling bins sat by the side of the road. Two held cans and plastic; two were packed with paper and cardboard.

The bins contain a household's usual assortment of recyclable flotsam and jetsam: a plastic Mott's apple juice container, a black plastic takeout tray, yogurt containers, innumerable cat food cans, an aluminum tray, and much more.

The material is trucked to a cavernous facility in Avon run by Waste Management Recycle America, a subsidiary of Waste Management Inc ., one of many such facilities run by Waste Management or other companies. Two connected warehouses are each big enough to host a Patriots football game, with plenty of room under the ceiling for punts.

The site handles a staggering 350 tons a day of recycled waste, six days a week , from 18 communities , most of them in this area, as well as from businesses. If you live in Avon, Braintree, Dedham, Halifax, Hull, Mansfield, Milton, Norton, Norwood, Plymouth, Stoughton, Walpole, Westwood, or Weymouth, your recyclable trash ends up here.

All but the paper and cardboard is dumped on a mini mountain of recyclable trash. It's a huge, messy mix. Tide detergent bottles rest next to dill-pickle jars. Presumably, the Hinckley Road cat food cans are in there -- somewhere. There's surprisingly little smell. Trucks that stink are turned away.

This is the domain of Austin McKnight , the facility manager , a no-nonsense type in a hardhat. He runs the site with a crew of 25 men .

It is here that the marvels of modern machinery are on display for anyone who ventures into McKnight's world. He's been here since the facility opened in September 2001, and he has a keen appreciation of what the machinery can do.

"You have to . . . do the kind of work we're doing here every day," he said.

Under McKnight's watchful eye, a front-end loader pushes the recyclable trash onto a broad, black conveyor belt that rattles along at an impressive speed and with considerable noise, carrying trash into the sprawling sorting contraption that fills most of one of the warehouses.

First, powerful magnets hanging above the conveyor cause cans -- and anything else made of steel or tin -- to fly up off the conveyor belt, as if by wizard magic. They bang hard against the magnet and are pulled overhead and away.

Next, glass containers, most of which have been smashed to pieces by their journey to this point, fall through holes in grates, where they end up in separate bins.

Computer-controlled cameras take pictures of what is left. In an instant, the computer uses the picture to decide what is plastic and what is not.

All the waste trundles toward a band of metal studded with holes. As a plastic bottle reaches the metal band, a computer uses the information in the photo to strategically blast jets of air through a select handful of the holes, hurtling the targeted bottle into the air and over a barrier. Now the plastic has been separated.

The machine is about 95 percent accurate, said McKnight.

Aluminum cans are the last sort. An "eddy current," which is an electric current induced by an alternating magnetic field, separates the aluminum from the waste stream.

What's left isn't much -- an odd assortment of toys, sometimes black plastic, which is not popular with recyclers, plastic bags, and other non-recyclable items.

The overall recycling rate for everything taken into the facility is about 97 percent , said McKnight. The 3 percent left is compressed and taken to landfills.

Paper and cardboard go through their own conveyor system for sorting. All along the system, men sort by hand, pulling out recyclables that the machine sorted incorrectly.

Once sorted, each recyclable is crushed into a compact cube and stacked throughout the warehouses. (Crushed glass is the exception and is loaded into containers.)

Piles of paper, of many different grades, sit stacked like so many giant blocks. They can weigh up to 2,400 pounds . Plastics, steel, and aluminum sit in their own piles.

From there, the separated recyclables are shipped out.

Glass stays in Massachusetts, at least for a little while. It goes to a plant in Franklin , where it is separated by color. After that, it is is sold to glass manufacturers.

Glass from food and beverage containers can be recycled over and over. About 90 percent of recycled glass is used for new containers, according to the federal government.

Paper can go to paper mills almost anywhere. From this site, most stays in the country, but some is shipped to Canada. Nationally, 81 percent of the paper recovered is recycled in paper mills; 16 percent is exported to foreign markets.

All the plastic from this site goes to North Carolina , where it is sorted by resin type. Recyclable plastics are marked with a number, 1 through 7 , which indicates the resin.

Milk and water jugs, which are made of a resin called HDPE , are highly valued, and often end up again as milk jugs. Some are used for flexible pipe or lawn chairs. The foreign markets for resins such as PET , used in soda bottles, is growing and more and more of it ends up in Asian markets, such as China .

Steel cans from this site go to Canada or Pennsylvania . They can be recycled into everything from more cans to automobiles. More than 1,000 facilities across the country make and process steel, with most located in the Great Lakes region or the South.

To feed this process requires individual efforts of the 360,000 households across the region, which each week invest their time and effort at the front end of the recycling process -- rinsing out cans, gathering up old newspapers, and hauling it all out to the curb.

Their effort benefits more than just the environment. The more paper that is recycled, the more money a town saves. And there's more that can be done.

"When you throw away recyclables, you are throwing away money," said Brooke Nash , a state Department of Environmental Protection branch chief . She stressed that recycling benefits people, towns, and the environment.

If communities recycled the paper products they throw away each year, they could save $52 million in trash fees they pay, she said, and might even make a few dollars in the bargain.

Paper, especially, is in high demand in countries such as China . Chances are, Nash said, that the cardboard box a new TV comes in this Christmas originally "left the US, went overseas, and was turned into another cardboard box."

Matt Carroll can be reached at mcarroll@globe.com.