The National Butterfly Center is a dream come true for butterfly lovers. Picture more than 200 species flying free across 100 acres of gardens, woodlands, and nature trails. Butterflies are drawn to the property by nectar plants. The plants produce the sweet syrup that butterflies rely on for food. Some of the insects, such as the ruby-spotted swallowtail, are found almost exclusively in this part of the U.S. Others, like the world-famous monarch, are just migrating through. Texas is located between the main breeding ground for monarchs, in the northern U.S., and the warmer climate of Mexico, where they spend their winters. —Allison Singer