There’s nothing new about urban u-pick farms, dairies, and other agricultural attractions. In fact, we almost expect them in places like Portland and Denver, where cities sprawl into vast farmland. But in the last five years, massive farming operations have also started cropping up in dense metropolises, like New York City, where you'd be hard-pressed to find a tree-lined block let alone an apple orchard.

Here are three major metropolitan areas with surprisingly rich urban farms that are a destination all on their own.

Phoenix
Believe it or not, crops like melons, squash, and lettuce thrive in Phoenix's triple-digit summer heat. Plus, the city’s mild winters make it ideal for growing oranges and lemons.

You’ll find farms scattered throughout Phoenix, but the highest concentration are on the Fresh Foodie Trail, a collection of 11 agricultural destinations in the East Valley. Don’t miss Agritopia, where you can enjoy a farm-to-table meal next to the urban gardens and purchase freshly picked produce from the farm stand. Or there's Schnepf Farms, known for its Peach Festival in the spring and Pumpkin & Chili Party in the fall.

Dairy cows do well here, too (as do pigs and goats), so you'll want to stop at Superstition Farm, where you can tour the farm and sample fresh milk, and The Pork Shop -- a third generation butcher shop -- which sells seven types plus brats, sausage, and fresh-cut chops.

Other highlights include the Queen Creek Olive Mill, where you'll learn how olives are pressed into oil, and Hayden Flour Mills at Sossaman Farms, which offers occasional tours and classes. In late winter and early spring, stop by The Orange Patch for fresh citrus and other local goodies.

New York City
New York may be one of the nation’s most densely populated cities, and -- combined with its volatile weather -- an unlikely location for urban farms. Yet according to a study conducted by Design Trust for Public Space, the city is home to more than 700 urban farms and gardens -- that’s almost three times the number of Starbucks franchises located in the city (which are in no shortage).

While most of these urban farms are private, a fair number are open to the public, including Battery Urban Farm at The Battery Conservancy, where you can learn sustainable farming techniques and maybe even sample a new herb or veggie. Randall’s Island Urban Farm introduces visitors to the concept of urban gardening with 80 raised beds of vegetables, two greenhouses, four rice paddies, a berry patch, an orchard, and a chicken pasture.

Brooklyn Grange Rooftop Farms grows more than 50,000 pounds of organic produce every year at its two locations, the Brooklyn Navy Yard Farm in Brooklyn and Flagship Farm in Queens. You can visit for free during the weekly open house, which takes place every Saturday from 11 a.m. to 4 p.m. from May 21 through October 29, 2016. The Brooklyn farm has beehives, too, and offers classes on beekeeping.

The Red Hook Community Farm -- a former asphalt playground in Brooklyn -- now grows more than 30 crops including arugula, beets, basil, and heirloom tomatoes. Drop by on Friday and Saturday mornings for free tours.

Oakland
There's an urban farming revolution going on in Oakland, inspired by Novella Carpenter, who co-authored the book Essential Urban Farmer with Willow Rosenthal. At her own local farm, Ghost Town Farm -- which has become a popular local attraction -- Carpenter keeps bees and chickens, tends to an orchard of 36 fruit trees, and grows tomatoes and other vegetables. She occasionally gives tours and conducts classes onsite.

City Slicker Farms grows fresh produce for the West Oakland community and educates families about healthy food choices. Although the farm stand is intended for local residents only, the farm does offer tours the second Saturday of every month from spring through fall, at a suggested donation of $10 per person.

Want to learn about urban farming? Schedule a visit or a class through Mushroom Maestros. You can even arrange to work on the farm in exchange for a crash course in mushroom cultivation. Or, check out the offerings at the Institute of Urban Homesteading, which range from gardening and food preservation to foraging and fermenting. The institute occasionally conducts local farm tours, too.

Bonus: Oakland has a walkable urban wine trail that features 10 wineries. Although the grapes are sourced from other parts of California, the wines are actually produced in renovated warehouse spaces in Oakland, several of which are on or near Jack London Square. Jeff Cohn Cellars, Brooklyn West Winery, Cerruti Cellars, and Rosenblum Cellars are among the wineries included.