No event has done more to shape the landscape of brewing in Minnesota than the 2011 passage of the so-called "Surly bill" that allows production breweries to sell pints of their own beer for consumption on site. The resulting proliferation of taprooms has opened up a bevy of imbibing options for Twin Cities beer drinkers. There are currently 25 taprooms inside the I-494/694 loop. As many as 10 more could open by the end of this year.

A taproom is like a bar inside a brewery. It's a place for folks to gather at the source and enjoy beer at its freshest and finest. Although the law allows it, most taprooms don't serve food. The brewers are too busy making beer to mess with running a kitchen. But food trucks are a fixture of the taproom scene. There is usually one parked outside to feed your need for food. Where food trucks aren't allowed, ordering in from nearby restaurants is often an option.

With so many taprooms in such a small area, putting together a brewery crawl is easy. Two burgeoning brewery districts, one in northeast Minneapolis and the other along the Metro Transit Green Line, let you leave the car behind to take in multiple taps by foot, bike or train.

Tour No. 1

With seven taprooms in a 2-mile radius, northeast Minneapolis is a beer lover's paradise. Many of them can be easily reached on foot. An easy bike ride will get you to those on the edges. There are three NiceRide stations nearby if you don't want to bring your own bicycle.

Indeed Brewing Co. is the anchor of the district and a good place to start your trek. The handsome taproom is always jumping. Decked out in custom oak paneling, it feels like the boardroom of a 19th-century lumber company. Tables scavenged from just such a business are carved with the signatures of famous figures such as Teddy Roosevelt. Picnic tables on the small patio make for nice summer sipping.

Indeed is best known for its hoppy Day Tripper Pale Ale. In the taproom, it's joined by an assortment of seasonal and taproom specials, including fruit- and spice-infused beers and nitro versions of the flagships.

Just across Central Avenue NE. from Indeed, you'll find three breweries within a couple of blocks of one another: 612 Brew, Bauhaus Brew Labs and Sociable Cider Werks. The 612 taproom has a trendy, retro-industrial ambience. Thick maple beams that support the high ceiling and a bar top made from repurposed bowling alley lanes give it a rough edge that is refined by gleaming, polished-stainless tanks and a cheeky Adam Turman mural. A stone amphitheater outside hosts frequent live music during the warmer months. At 612 the specialty is sessionable hoppy beers, beers that have some zip without taste-bud-scraping bitterness. Unrated Rye IPA has only moderate rye flavor, coming in as a slight, spicy bite in the finish. Citrusy hop flavors take the lead, supported on an ample cushion of grainy-sweet and vaguely biscuit malt.

The soaring, early-20th-century industrial space of the Bauhaus Brew Labs taproom has the energy of a German beer hall, with long, communal tables that encourage social interaction. Splashes of bright color add a liveliness to match the buzz of the crowd. Bauhaus Brew Labs is a family-friendly place with toys and games to keep the little ones entertained.

Bauhaus beers are based on classic lager styles with slight tweaks like nontraditional hops to give them a modern twist. Wagon Party, a malty, amber, California common style brew, is a must-try, as is the Stargrazer German-style black lager.

Sociable Cider Werks specializes in beer/cider hybrids that they call "graff." They use only Minnesota-grown apples sourced from Pepin Heights Orchard in Lake City. Because culinary apples often don't provide the bittersweet and tannic elements required in a balanced cider, they use grains and hops to fill in the missing notes. Spoke Wrench is a great example. This stout and cider blend delivers the roasty aromatics of an Irish stout, and a flavor that is all about the apples.

The taproom is part factory, part hillbilly honky-tonk. Rocking chairs, rough-hewed wood and tables made from giant wire spools give a simple, countrified flair that almost makes the brewery behind the bar look like a moonshiner's still. Live music is a regular feature.

A mile to the west is Dangerous Man Brewing Co., one of the hottest beer destinations in the Twin Cities and the first to follow a taproom-only business model. You won't find Dangerous Man anywhere but at the source, and people turn out in droves to drink it. On weekdays the atmosphere is calm and sociable. On weekend nights, it's not unusual to see a line out the door.

The tap list at Dangerous Man is constantly changing, although a couple of beers have become semiregular offerings, including a deliciously rich chocolate milk stout. But as the website says, there will always be "a dark one, a light one, a hoppy one and a strong one."

Head a mile north on Central Avenue to reach Fair State Brewing Cooperative, the state's first co-op brewery. Members have an ownership stake in the brewery that gives them voting rights and exclusive access to events and special-release beers. Single and household memberships are available.

Sleek lines and exposed, buff brick give the deep, narrow Fair State taproom a contemporary art gallery vibe. A recent exhibition of beer-themed posters only served to heighten the effect. The lineup of well-crafted beers includes a lovely hefeweizen and pilsner. The LÄCTOBÄC series will appeal to fans of sour beer.

Northgate Brewing Co. is the farthest-flung of the Northeast breweries. It's located a mile and a half east on Harding Street just south of Broadway. Northgate specializes in classic English ales. From bitter to brown to a chewy sweet stout, the beers exhibit the characteristic nutty/toffee malt profile and buttery/fruity yeast notes that mark those styles. The brewers recently gave in to pressure and did something they said they would never do. They brewed an American-style double IPA called Here's Your Frackin' IPA. It's surprisingly light and drinkable given its 8 percent alcohol and 100 bittering units.

Tour No. 2

Those who prefer to ride the rails can take in a growing number of taprooms along the Green Line that runs between the two downtowns. With a modesty befitting the city, St. Paul's so-called "Green Line Brewing District" has developed more quietly than its counterpart in Northeast. But quiet doesn't mean dull. The district encompasses some of the metro area's unique breweries, from Surly Brewing at the edge of Minneapolis to Tin Whiskers in downtown St. Paul.

Surly Brewing Co. is just a short walk from the Prospect Park station. It's hard to argue that there is a more monumental cathedral of beer and brewing in the Twin Cities than the new Surly facility. Beer is the focus here, literally. Upon walking in the door, guests are greeted by the conical bottoms of 600-barrel tanks poking through the ceiling of the fermentation cellar. Every vantage point in the building offers unobstructed views of the impressively massive brewhouse.

Food is not forgotten. Surly is one of two Twin Cities taprooms with a kitchen. Chef Jorge Guzman has crafted a menu of deliciously upscale bar food for the beer hall, including a delicious charcuterie board with house-made meat specialties. The Brewer's Table restaurant upstairs features fine-dining fare designed from the start to pair with Surly beer. And how is the beer? Well … it's Surly.

From the Raymond Avenue platform, head north along Hampden Avenue to Bang Brewing and Urban Growler Brewing Co. The two are located just steps from each other.

The corrugated steel corn crib that houses Bang Brewing looks out of place among the warehouses of this industrial district. But the only grain in this bin is used to make beer. The round space feels bigger on the inside than it looks from outside, but it is intimate. The taproom is right in the brewery. The bar rolls out of the way when there is work to be done. Additional seating on a small patio helps to handle the overflow. Owners Sandy and Jay Boss Febbo are usually minding the taps. You won't find more genuinely nice barkeeps anywhere in the metro area.

Bang's collection of 100 percent organic beers focuses on drinkability. There is nothing "out there" or over the top. Each beer sports a simple, one-syllable name that bespeaks that sensibility. One of my favorites is King, an English-style mild ale with toffee and biscuit malt, restrained bitterness, earthy hops and delightful orange/apricot yeast notes.

Upon entering the Urban Growler taproom, the first thing you notice are three copper-banded serving tanks towering at the center of the room behind the bar. They anchor the space, making it clear that beer is the focal point of the bustling, social beehive buzzing all around them. Urban Growler was the state's first female-owned and -operated brewery. Owners Deb Loch and Jill Pavlak believe in bringing people together through beer. They conceived of the taproom as a place where people from all walks of life can sit down and get to know one another. A large patio makes this a great summer spot for just such activity.

Urban Growler was also the first taproom to feature its own kitchen. Chef Paul Suhreptz serves up a small menu of beer-friendly foods, such as Reuben or Cubano sandwiches and homemade buffalo-blue cheese potato chips. His signature pork carnitas are made with the brewery's Smoked Chipotle Porter.

Get off at the Fairview stop to visit Burning Brothers Brewing, the state's only gluten-free brewery. The professional brewing dreams of home-brewing partners Dane Breimhorst and Thom Foss were shattered when Breimhorst was diagnosed with celiac disease. They picked up the pieces and set out to make the best gluten-free beer possible.

The Burning Brothers beers are surprisingly successful. Breimhorst applied skills learned as a chef to combine ingredients in ways that counteract the unpleasant flavors often associated with the use of alternative grains such as sorghum. The results are remarkably beer-like. The flagship Pyro, a hoppy American pale ale, is always available at the taproom. Rotating taproom-only selections include an IPA, a stout and some fruity shandies — blends of Pyro with different fruit juices — among others.

The last stop on the Green Line tour is Tin Whiskers Brewing Co., a hop, skip and jump from either the Central or Midway platforms in downtown St. Paul. The electrical engineering background of the founders infuses the brewery's identity. The name Tin Whiskers refers to tiny hairs that grow from metal surfaces in electrical devices, causing short circuits. The beers have names like Short Circuit Stout and Ampere Amber. The mascot is a robot.

The taproom itself has the feel of an electrical lab. Full walls of windows bring in loads of natural light. Long beer-hall-style tables and an assortment of board games encourage social interaction. So guests don't forget where the beer comes from, the brewery is visible behind the bar, underlining the overall industrial feel of the place.

The tap list includes a year-round wheat beer, IPA and stout as well as various seasonal beers and taproom-only specialties.

Michael Agnew is a certified cicerone (beer-world version of sommelier) and owner of A Perfect Pint. He conducts private and corporate beer tasting events in the Twin Cities, and can be reached at michael@aperfectpint.net.