Traveling can be one of the best experiences a person can have. Exploring a new city, country, or culture can be both exciting and life changing, yet we often don’t stop to consider the ecological impact of our travels. In the 1950s, the world experienced over 25 million annual tourists (i.e., overnight visitors). By 2015, according to the Center for Responsible Travel, that number increased to nearly 1.2 billion---contributing $7.2 trillion to the world’s GDP. Some countries, though, are working towards making their cities and tourist-friendly hot spots as sustainable as possible. For travelers with a desire to do good, these five destinations in the U.S. will speak to your eco-friendly heart.