There are no Estes Park vegetarian restaurants. What? None? That doesn't mean Estes isn't veggie friendly, just that there aren't any restaurants with no meat on the menu whatsoever.
My diet is mostly vegetarian, and I've never had a problem finding anything to eat at just about any restaurant in Estes Park. Most restaurants offer several vegetarian dishes, and they're usually good, too- that is, you won't find many restaurant owners here who think American cheese on white bread = "vegetarian."
That said, if you have a serious aversion to meat, you should avoid any of the restaurants on the steakhouse list (even though a lot of them offer tasty salads).
These are some of the most vegetarian-friendly places in Estes Park:
The Baldpate Inn 4900 S Hwy 7, (970) 586-6151, $$ All-you-can-eat soup and salad bar with homemade bread and scrumptious pies. Beautiful, rustic building with view. World's largest key collection! Closed in winter.
The Egg & I 393 E Elkhorn, (970) 586-1173, $ A reliable breakfast favorite with a huge assortment. Also serving lunch. Go early, though, because the place gets packed!
Good Fortune Chinese Restaurant 160 1st St., (970) 586-5119, $$ Hit and miss Chinese food. Some dishes are great, others just okay. Usually not too crowded.
Hunan Restaurant 406 W Riverside Dr., (970) 586-8287 An old standby for quick Chinese and take-out. The lunch specials are very affordable. Best Chinese in Estes. Map note: the online maps were off, so I pointed to Mountain Woodcarvers (next door) instead.
Mama Rose's 338 E Elkhorn, (970) 586-3330, $$ Good Italian food in a nice atmosphere on the Riverwalk. A good choice for families- last time I ate here I couldn't eat anything else for three days because I was stuffed! First it was the salad, then the bread, then the huge entrée, the dessert… They have very affordable winter specials, and they're just nice people. They offer explicitly vegan options.
Nepal's Café 184 E Elkhorn Ave., (970) 577-7038, $$ One of my favorites in Estes, Nepal's Café has some seriously good food, just like your Nepalese aunt used to make... authentic and yummy. Watch for the buffet.
Notchtop Bakery & Café 459 E Wonderview, (970) 586-0272, $$ Notchtop has some reliably tasty food and even better baked goods.
Poppy's Pizza and Grill 342 E Elkhorn, (970) 586-8282, $$ If I had to save one restaurant in Estes Park from burning, this might well be it. The food is great and the owners make everyone feel like a part of the family. The winter specials are a great deal. The one drawback is that it is super busy in summer. Serves pizza, sandwiches, soups, and salad.
Shakes Alive! Fruit Shakes 513 Big Thompson Ave., (970) 577-7007, $ Tasty smoothies and fruit shakes made to order. Lots and lots of flavors to choose from and the owners are super-friendly. Some small sandwich items too.
The Sundeck 915 Moraine Ave., (970) 586-9832, $$ A rustic mountain atmosphere, nice people, and good food. Some of the best trout around.
Sweet Basilico 430 Prospect Village Dr., (970) 586-3899, $$ EXCELLENT Italian food. One of the best restaurants in Estes. They are always packed, so reservations are a good idea. (Although, since they just moved to a larger location, this may be less of a problem now. Here's hoping they do just as well in the new location.)
Thai Kitchen 401 S St. Vrain, (970) 577-7112, $$ Excellent Thai food. But not for wimps! Their "mild" seemed pretty hot to me, but it was delicious.
My favorite? Well, I pretty much like all the restaurants listed here, so it would be hard to say that one of them was my favorite. BUT, if I had to pick one for a vegetarian, The Baldpate Inn, with its all-you-can-eat soup, salad, and bread, can't be beat. And the pie... mmm... (The Baldpate is closed in winter; Poppy's has the next-best salad bar.)