Mar 15, 2016 - 6:03 PM
I'm not sure if you've seen our page yet, but you'll find a lot of information there: myswissalps.com/ jungfraujoch.
I think the diagram says you need at least an hour for the attractions and another hour if you want to do snow activities too. I would say you need two hours even without the snow activities if you want to take your time (recommended anyway at that altitude) and have lunch too. You don't need tickets, except for the snow activities.
There's a self service restaurant. The souvenir shops may sell snacks, but I don't know if they qualify as a proper lunch. You can bring food yourself if you wish.
I haven't been up there since Lindt opened but it should be easy to find. There are signs to find the way. I'm sure they want you to find their shop :-)