The Columbia Icefield is a gigantic icefield over 300 meters deep in places and covering over 300 square kilometers of land around the highest peaks of the Canadian Rocky Mountains. Most of the Columbia Icefield is inaccessible and seen by only the foremost adventurers. The Athabasca Glacier, one of several glaciers spurring off the icefield, is a notable exception. Located right off the Icefield Parkway near the boundary of Banff and Jasper national parks, Athabasca Glacier is one the most visited glaciers on the planet. Many visitors will view the glacier from a far distance from the Discovery Center, or pay nearly $100 to ride a Brewster bus onto the glacier itself. However, a short hike from a small parking area a kilometer away from the Discovery Center leads basically to the toe of the Athabasca Glacier, and is free with national park admission.
The trailhead to Athabasca Glacier is not signed well, but is pretty easy to see from the open and barren terrain in this area. A parking area is right off the Icefields Parkway on the right side if you are coming from Jasper (left if coming from Banff); travel down the hill to the right to get to another parking area where the trail begins. While the trail is not long, it is noticably longer than most of the other roadside attractions on the Icefield Parkway, at a relatively higher elevation (up to about 2,000 m above sea level), and is significantly more exposed to cold mountain wind and any weather systems that can form in this mountainous region on a moment's notice, making the relatively short walk more physically taxing than it may appear in writing. Water is not available at the trailhead or anywhere on the trail. A small vault toilet is at the trailhead -- expect a long line if you need to use it.