It's not glamorous, but the greenest way to spend your vacation is to stay close to home. Passing up on air travel cuts down on carbon emissions, and the less you use the car, the better. Plus, you'll save money on lodging, which can be put towards a home or garden improvement project like planting flowers or installing solar panels. Instead of traveling the globe to find adventure, set off on a bicycle day-trip in your own town: The slow journey is half the fun: you'll see things you've never noticed before and get a better appreciation for your own neck of the woods.