Ah, spring — a time of renewal and revitalization. Of course, for many of us, it's also a time of hellish pollen fields, itchy eyes, and nonstop sneezing. And, as a new ranking from the Asthma and Allergy Foundation of America (AAFA) reminds us, some parts of the country are hit a lot harder than others.Sure, there's the amount of pollen that's naturally floating around. But this particular allergy ranking also looked at other often-overlooked factors: Are there any board-certified allergists nearby? How easy is it to get your hands on allergy and asthma meds? All of these influence how difficult it might be to live in various areas when seasonal allergies hit.Using those criteria, AAFA's experts ranked many of the country's major cities. Click through to see the 15 in which it's especially rough this time of year for the allergy and asthma sufferers among us. Before you check out the list, remember that there are a ton of ways to manage your allergy symptoms. And a chat with an allergist can make the difference between a totally congested spring and actually enjoying being outside.