Apple's iOS 7 changed the way mobile Safari manages multiple open pages. The current version presents the list as a "fan." Scroll through it with a swipe of your finger to quickly browse all open pages. Did you know you can also reorder those pages? You can, and here's how.
Simply tap and hold on the page you'd like to move for about a second. It will become slightly more pronounced in appearance while the others fade into the background bit. Now you can drag that page to any position on the list that you want.
While we're at it, there are two ways to close a page. Either tap the "x" in its upper left-hand corner, or simply swipe it to the left.