Running Shoes
Most backpackers think they will be wearing flip flops the entire trip and that they would have no use for running shoes. In fact, many destinations have physical activities available for backpackers that are more enjoyable with the proper foot wear. Whether it is going for a jungle hike in South East Asia, or if you are going mountain biking in Argentina, you will be glad you brought you running shoes.
Running shoes are also a great alternative to flip flops when you are doing city walking tours. Some walking tours can be several hours, and flip flops eventually start to wear on you.