Logan Airport, New England's primary international airport and 48th busiest in the world, resides mainly in East Boston (though part of the airfield itself lies in Winthrop). There has been continual controversy surrounding Logan, as constant conflict with the Massachusetts Port Authority has been a source of bitterness among some local residents since its inception. One expansion of the Airport resulted in the loss of Wood Island Park, a green space designed by the noted landscape architect Frederick Law Olmsted. The expansion of Logan Airport in the late 1960s and early 1970s displaced families along Neptune Road, which is now used for warehouses and rental car property. The airport has since implemented four "airport edge buffers," which include parks and greenery to appease residents.