The Seward Highway offers a range of ice climbs all the way from Anchorage to Seward. Climbs range from WI2 - WI6 amd there are many mixed lines. The climbs usually form around late November and last through late March or until it warms up. The only concern you will have on some climbs are the cars passing five or ten feet from you. Just watch yourself and you will be fine.
Please do not dry-tool on existing rock climbs along the highway.