The Sierra Club recently created a subway map that includes every one of the United States national parks. The Sierra Club is America's largest and most influential grassroots environmental organization. Although the parody is "incredibly not to scale" and is also sheer fiction -- just in case you were thinking about taking the green line toThe Sierra Club recently created a subway map that includes every one of the United States national parks. The Sierra Club is America's largest and most influential grassroots environmental organization. Although the parody is "incredibly not to scale" and is also sheer fiction -- just in case you were thinking about taking the green line to