Roads 944 Outdoor recreation 554 Central business districts 450 Trails 178 Recreation areas 145 Historic sites 132 Cities and towns 129 more ... Subways 114 History 95 National parks and reserves 88 Public lands 61 Express highways 59 Local transit 59 Recreational use 59 Railroads 56 Hiking 55 Parks 51 Scenic byways 51 Historic districts 47 Historic buildings 46 Heritage tourism 43 Transportation 38 Motor vehicles 33 Routes 32 Bicycle trails 31 Boats and boating 29 Business enterprises 29 Administrative and political divisions 25 Forest roads 25 Commuting traffic 24 less ...