No summertime drink is as satisfying and easy to make as refreshing lemonade.
In a small saucepan, combine sugar and 2 1/2 cups water. Bring to a boil over medium-high heat, stirring until sugar is dissolved. Remove from heat; let cool.
In a punch bowl or large container, combine the lemon juice, sugar syrup, remaining 4 cups water, and ice. Stir well to combine. Thinly slice remaining lemon, and add to lemonade. Serve.