Fishing, hiking, trails, camping, hunting, wildlife, glacier cruising.
Visitors Center open daily 11:30am-9:00pm
There is a ton to see and do here, so consider making this a several day visit (there are B & B's in Gustavus, and like a true Alaska town there is no mall or fast food) or camp at one of the sites.
If you only have 1 day here then you have to choose land or sea. Our recommendation is sea (and this is a tough choice). We have been to glaciers, even hiked glaciers, but I have never in my life seen anything as majestic and moving and Glacier Bay. My son, who usually talks non-stop, was struck mute. While we took our sea tour we saw tons of seals, which was fun, but the glacier itself is something that can't be described. A park ranger was on our boat and gave a great presentation about the history of the area, native tribes, habitats and wildlife, and geology. It was informative and witty. I believe a park ranger is present on all boat tours.
If you have the time don't miss the land part. There are tons of trails and hiking. You can grab a map and go it on your own, or take guided hikes with a ranger or volunteer. Stop by the Visitor Center in the morning to go on a group guided hike. The Visitors Center also offers movies, lectures, walks, and rangers programs throughout the day. These activities are free. The center also has checklists/scavenger hunt type lists you can check off for plants and animals during your hikes/walks.
Check out the website before visiting to get schedules, maps to campsites, etc. There is something for all outdoor lovers here. The fishing is great to.