The amazing view of the bay and GG bridge (IMPORTANT: be certain to ask for a table by the window when making reservations) alone make Greens the #1 choice for vegetarian/health-conscious out-of-towners visiting. They do have a nice vegetarian food selection, but the food itself isn't, in my opinion, outstanding enough to warrant high prices. The restaurant is beautiful and feels luxurious so if that is important to you you will probably like it here. They source some ingredients from a farm in Marin so that is nice.
The big problem is they seem to be pretty un-sympathetic to vegan customers, with really limited vegan offerings. It doesn't make much sense. As a vegan, I would not go here except with guests. That's disappointing.
I think this is a better option for high-end vegetarian dining than its main competition, Millenium downtown, because it's easier to park, the restaurant is more spacious and beautiful, and the view is amazing.
If it's your first time here, the Fort Mason buildings can be a little confusing. Inside the gated parking area, stay along the row of buildings to the left and keep walking towards the water. Watch for signs and you'll find it, disguised from the outside like all the other formerly military buildings.Pros: View, Ample parking
Cons: Very limited vegan selection, Expensive