There's always a good season to visit the US's most under-rated city

Average temperature: 9 degrees Celcius minimum, 6 maximum

WHY: After a long cold winter, Chicago wakes up from its slumber. The baseball's starting - Chicago has two iconic teams; and the tulips are blooming in time to wander the city's most famous shopping street, Michigan Avenue. Chicago's Lakefront Trail beside Lake Michigan becomes a magnet for walkers, joggers and bikers.

HOW: With sunny days that won't rise in temperature above the mid-teens, shopping mania hits Chicago. Get to the Magnificent Mile along Michigan Avenue. There are more than 275 restaurants, 460 stores and some of America's most iconic buildings. It's not only tourists who come, locals love spring here too. The Mile pulsates with raw energy any time of the day or night. Street markets also open all over Chicago's 77 neighbourhoods from April. Though nothing screams spring in Chicago more than the Chicago Cubs, the city's most beloved baseball team. Watch them play at America's second-oldest stadium, Wrigley Field, established in 1914. Spring's the best time to explore the city's hottest dining scene, among historic factory buildings of the West Loop, the former meat-packing district. Try out 18 eateries and three bars at the Time Out Market, or Chicago's best pasta at Top Chef winner Sarah Grueneberg's Monteverde Restaurant. Sleep a short stroll from the Magnificent Mile in a 100-year-old hotel which harks back to Chicago's Gilded Age. The Pendry Chicago has a rooftop bar/restaurant with views back over Michigan Avenue.

Average temp: 19 min, 29 max

WHY: Chicago comes alive in summer with a heady mix of outdoor activities built around its lakeside beaches and parks, and some of America's best music festivals. And summer's when locals frequent their impressive collection of rooftop bars and restaurants.

HOW: The Chicago River flows right through the city: in summer it becomes an epicentre of activity. Take a kayak tour, or a boat tour (especially the Architecture River Cruise which showcases the city's world-famous buildings), or traverse the Riverwalk, stopping along the way at the sun-drenched waterfront patios of bars and restaurants. Chicago might be landlocked, but there are 24 sand beaches along 45 kilometres of riverfront beside Chicago's CBD. Take a paddleboard tour, or a yacht cruise, or walk the 29-kilometre-long Lakefront Trail. And there's a festival somewhere you'll want to check out: like the world's largest blues festival (Chicago Blues Festival), or the mega-iconic, four-day Lollapalooza music festival. The best rooftop bar/restaurant to see the wonders of the city under the sun is Cindy's Rooftop, atop the impressive Chicago Athletic Association Hotel in The Loop. You'll find Chicago's finest cocktails, and freshest oysters, along with the hippest outdoor dining vibe. For something more intimate, taste fine Mediterranean cuisine on a stunning terrace overlooking the city skyline at Aba. Keep those city views flowing at the historic, 452-room LondonHouse Chicago hotel, which also overlooks the river.

Average temp: 8 min, 17 max

WHY: Locals will tell you that fall (autumn) is the best time to see Chicago. It's less crowded, days stay warm but nights are crispy and cool, and the city is a wonderland of autumn foliage as Chicago's 600-plus parks break out in reds, oranges and yellows. It's also when the best food and wine festivals hit town.

HOW: Any proud Chicagoan will tell you Chicago is better than New York City, particularly because of its green spaces. The biggest (and best) is Lincoln Park, which is one-third larger than Central Park at 500 hectares. It's the best place to see the nature show as maple, elm and ash trees explode in colour. There's also a conservatory, a zoo, a rowing canal, two museums and a bird sanctuary. In a city famous for festivals, be here in autumn if you fancy festivals of the culinary variety, including Chicago Gourmet, one of America's most distinguished food festivals. Autumn is football season; Chicago goes CRAZY for its famously under-achieving Bears (NFL). There's no bigger sports-loving city on Earth. On game days, every sports bar in town is a wonderland of sports-crazed, fun-loving mid-westerners. But the best atmosphere is at sports bar Timothy O'Tooles. Or try Lottie's in hipster hang-out Bucktown. Football season is the best time to try the city's famous deep-dish pizza - and it doesn't get better than Pequod's Pizza. (Be warned, choose well, bad deep-dish pizza is awful). Stay at Hotel Lincoln with views over Lincoln Park and Lake Michigan, from your room and its J. Parker rooftop bar.

Average temp: -9 min, -1 max

WHY: There's no sugarcoating it, Chicago gets VERY cold during winter. But it brings a different sort of magic to the city. Christmas is straight from a Disney movie. And when Lake Michigan freezes over, the place looks surreal. Chicagoans sure know how to bunker down in the city's hundreds of cosy restaurants and bars.

HOW: It's cold outside, so stay indoors. There are more than 80 museums - try one of the largest science museums in the US, the Museum of Science & Industry, or the Chicago History Museum. Art aficionados will love winter. Check out one of America's oldest and largest art museums, the Art Institute of Chicago, or the Museum of Contemporary Art. Though there's art all over: entire neighbourhoods, like River North, are full of it in former warehouses. And there's a diverse theatre scene with many Tony Award-winning theatre companies, not to mention the options for comedy fans who'll already know the Second City spawned America's greatest comedians, like John Belushi and Bill Murray. Winter's the perfect time to spend entire afternoons at the city's steakhouses. The best of them is Gibsons Bar & Steakhouse, a Chicago institution - take a seat at the bar and enjoy the human traffic. And try another icon, Tavern On Rush, just across the road in Chicago's most fun neighbourhood, the Gold Coast. The bonus here is it's in Thompson Chicago, an underpriced, over-delivering hotel right at the heart of the best action in the city.