What about Zell am See for your overnight. That is where we are doing the Grossglockner from.

If you're talking about May you might be out of luck this year. There are tons of snow on the main crest of the Alps, and that's where the Grossglockner Hochalpenstrasse is. They will hardly open before end of May.

Ingo, good information, we would be doing the drive around May 27. If it is open Michele says she will start @ Zell am. I assume she goes toward Lienz from there, is that correct? Any idea about how long the trip takes? I will write one of the otel owners to see if they think it will be open then.I wonder if I'll have the same problem going to the Eagles Nest.

All depends on the weather in the next weeks. Right now it took a turn to colder and new snow, so I am not too optimistic for an early opening of the Grossglockner Hochalpenstrasse. But I'll keep my fingers crossed The official homepage says "opens early May" - which is VERY optimistic IMO. Last year we had an unusually warm and dry April on top of a winter with less than average snow, so they could open end of April. That's probably where they get their opinion from ...

Anyway, the drive is from Zell am See via Bruck - Fusch and the wildlife park Ferleiten to the toll gate up to Edelweissspitze (small detour on a very narrow, steep, windy road) - the first highlight. Then follows the tunnel, from there it goes downhill - take the road to Kaiser-Franz-Josephs-Höhe with view of Mt. Grossglockner and the glaciers. The food at the self-service restaurant there is awful, I recommend either a short hike (Panoramaweg or Gamsgrubenweg) to one of the mountain restaurants/huts or an earlier stop at Kasereck. Don't know of one of the others is open end of May, though.

I would drive as far as Heiligenblut, see the pilgrim church there, then turn around and drive back to Zell am See - same route (you only pay once - 32 Euro is the day ticket).

Another option is to drive further down the valley to Winklern, over a low pass to Lienz, and back via Felbertauern tunnel - Mittersill to Zell am See. They have a combined ticket that includes the toll for the Felbertauern tunnel as well for 38 Euro, I think.

The latter option would be a fine full day excursion, the earlier one without going to Linz would take 4-5 hours, I'd say.

No idea about Eagles Nest.

What ingo suggested.
From my subjective point of view, it is "worth" to take the Grossglocker Rd. back same way. Not only because the ticket lets you do that, but the vistas are not all the same when you go back because you see them from a different perspective. It's also good when you have 2 drivers, so one can enjoy the scenery each way without caring about driving.
As the Grossglocker Rd. is a private road, you can expect it to open as soon as it can be driven safely without delay. But not sooner.
IMO, the time short after opening is the most spectacular, with spring in full bloom in the valleys and the mountains still covered solidly with snow.

Even from Halstatt, this would be considered a day trip, and does not require to change hotels.
Though you will appr. drive 1.5hrs to get to the beginning of the Grossglocker Rd. and back to Halstatt - but through very nice scenery.

The alternative return route via Felbertauern tunnel which ingo mentioned is much less spectacular than the Grossglockner Rd.

Thanks for the info Ingo. I appreciate it. I can plan some other day trips now just in case the road is not open.