Not only is the Lincoln Park Zoo open every day of the year, it's also 100 percent free to visit. Get cozy while you check out the lions, tigers and bears, and be sure to head back in December, when the grounds are illuminated with colorful holiday lights for ZooLights.
Make it a date: Once you’re done looking at the animals, grab a bite to eat at nearby Cafecito in Lincoln Park. The Cubano sandwich is less than $12 and one of the best versions in the city. If you need a jolt of energy to keep the romance going, order the restaurant's namesake drink—a Cuban espresso.