Is there anything more wonderful than a stack of buttermilk pancakes dripping with golden maple syrup?

How about seeing how the sweet syrup is made and then tasting the final product?

Every spring, maple producers across New England begin collecting sap from sugar maple trees and boiling it down into syrup, often using the same methods that have been employed for centuries.

Don't wait too long to travel there, though, because the sap is already flowing.

Vermont and New Hampshire will be celebrating their annual Maple Weekend on March 24-25, when about 200 sugarhouses across both states will be open for free tours, tastings and demonstrations.

The sugaring season runs roughly from early March to late April, but the timing can be tricky. Optimal sap flow requires temperatures of below freezing at night and 40˚ to 45˚ Fahrenheit during the day. This freezing and thawing pattern builds pressure within the trees, which causes the sap to flow.

Last year, more than 4 million gallons of maple syrup were produced in the United States, and Vermont trees were responsible for nearly 2 million gallons. Neighboring New Hampshire produced 154,000 gallons.

While New Hampshire and Vermont have a few large commercial operations, most syrup is produced on small to midsize family-owned farms. Both states are dotted with picturesque sugarhouses, white steam billowing from their cupolas.

Regardless of the size of the operation, the process of collecting sap and boiling it down into syrup hasn't changed much since the indigenous populations in New England taught their methods to European settlers.

The trees are tapped in midwinter, usually in February. Tapping involves drilling a hole in sugar maple trees with trunks at least 10 inches in diameter, and inserting clean taps.

Traditionally sap was collected in buckets hung on trees, but it's more common these days to see plastic tubing snaking from tree to tree, leading to a collection container or directly into the sugar shack. (Some farms use both methods.)

Even large sugaring operations refer to the building where sap is boiled as a sugarhouse or sugar shack. The rustic wood buildings are often built by hand, and most have an open hinged roof to ventilate the sweet steam produced in the boiling process. It takes anywhere from 40 to 60 gallons of sap to produce one gallon of syrup.

Maple syrup lovers who can't make the weekend celebrations can still visit these beloved sugarhouses any time of year. Just call in advance to let them know you're coming. That's because Mother Nature is in charge of the timing, and when she's done, so is the season.

Here are a few of our favorite farms to visit in season. The tours are all free, and of course the farms will have their maple products on sale.

Silloway Maple in Randolph Center, Vermont, has been producing maple products since 1942 and participating in the Maple Weekend for the past five years.

"We've had visitors come who actually think syrup comes straight out of the tree," says Bette Lambert, co-owner of the family business.

Bette's son Paul Lambert and his cousin John Silloway are the third generation to run the farm, which last year produced 3,500 gallons of syrup from 6,200 taps. In all, 22 members and four generations of the Lambert-Silloway family participate at varying levels in tapping, collecting, boiling, bottling and making maple products.

It's all done in a bright red sugarhouse at the end of a muddy road in rural Vermont. The simple wooden structure belies the modern technology employed within: The five-year-old sugarhouse is solar-powered and sports shiny new equipment alongside a cast-iron wood stove.

Silloway farm will be firing up their wood stove for Maple Weekend and doing tapping demonstrations every hour. Kids can enjoy hayrides, a petting zoo and tractor trips into the woods to collect sap. Bette Lambert will be serving sugar on snow, donuts and syrup-boiled hot-dogs.