This picturesque ravine, hidden in the heart of St. Paul, was once home to hundreds of immigrants; now it's an urban oasis of trails winding between steep wooded cliffs. Once a year it transforms into a bustling arts fair (June 6 this year), but mostly it's a haven of peace, quiet and bird-watching, just steps from the city. Once you've gotten into your stride, keep going; the Bruce Vento Regional Trail connects Swede Hollow to Phalen Park and beyond. swedehollow.org