One of the easiest ways to plan a travel is to carry a DIY Veg kit. All you would need is a proper plan to keep you wonderfully full and fit as you hit the road. It is not always chips and cola that have to bear you company. Having a well stocked food supply during your trip can also ensure you are not lured by the junk available at wayside eateries. It will also help in solving the ‘what to eat’ dilemma that confronts most travelers especially when there is nothing sensible to eat. Keep a stock of Tupperware boxes, small knife, small can opener, spoons, forks, carrot, cucumber, apples, nuts, juice cans, fried gram to make a perfect snack during travel.
There are many such websites which give the list of restaurants serving vegetarian food across the world.
Guide to Indian Vegetarian Restaurants
For Vegan/ Vegetarian/ Veg Friendly Stores and Restaurants
List of airlines with Vegan inflight meals http://www.veganworldtraveller.com/airlines/list-of-airlines-with-vegan-inflight-meals/