In a cold, wet field two hours’ drive west of London, there’s no mistaking the huddle of ancient shapes that emerge suddenly on the horizon, back-dropped by a distant cluster of leafless trees. Until recently, any first encounter with Stonehenge, that legendary keeper of Neolithic secrets, could prove deeply underwhelming. Two traffic-snarled highways have encroached on the brooding rocks, robbing them of their scale. Now that’s changing. The site’s custodians have unveiled a $44 million visitor center and a radical remodeling of the landscape that will reconnect the circle with the atmospheric terrain it has occupied for more than 4,000 years. Here’s a report.