In the past decade, the National Park Service has added 10 parks to its collection.
They commemorate World War II, a War of 1812 battle in Michigan, a 1944 ship explosion in California and an 1864 massacre of American Indians in Colorado. They mark an ancient volcanic landscape in Idaho and the birthplace of President Bill Clinton in Hope, Ark.
Over that same period, Delaware leaders have pushed -- unsuccessfully, so far -- to get the state's first national park.
They've studied and rewritten the proposal several times, paring it down to a collection of just six sites and a promise to be "budget-neutral."
"We've trimmed the sails a little bit so the scope of the park won't be as expansive as was envisioned in the last administration," said Sen. Tom Carper, D-Del., who has pressed the idea since 2002.
Yet the idea faces a Congress reluctant to expand the size and expense of government, especially in light of a $7 billion to $9 billion backlog of maintenance projects at the nation's nearly 400 existing parks.
"Even if it's budget-neutral, that still adds to a list of areas that need to be maintained," said Spencer Pederson, spokesman for the House Committee on Natural Resources, which will review a companion bill sponsored by Rep. John Carney, D-Del.
Carper said the cost is minimal relative to other national parks and can be covered by other cuts.
"Whatever the cost is -- $600,000 or $400,000 -- I have an obligation to work with my colleagues to offset that," Carper said.
Part of Carper and Carney's argument boils down to pride: Delaware should have a national park because every other state does.
"Delaware has as much to offer in terms of history and culture as most other states have in their national parks," Carper said.
Even Puerto Rico, Guam, the U.S. Virgin Islands, Northern Mariana Islands and American Samoa have national parks.
That's not a bad argument, said Alan Spears, legislative representative for the nonprofit National Parks Conservation Association.
"We're looking at the only state in the union that doesn't have a national park," Spears said. "It's not just another park. It's the first park for the First State."
"We had a significant role [in the founding of the nation], and not enough people know about it," Carney said.
Many tourists make it a goal to visit every national park, in part because they're free and well-maintained, said Kurt Repanshek, editor of the National Parks Traveler online magazine.
"There are a lot of people who enjoy history, learning about the country, and the historic parks are a big draw," Repanshek said.
Jim Lardear, spokes- man for AAA Mid-Atlantic, said a Delaware park could attract a portion of the tourists who visit Independence National Historical Park in Philadelphia or other Colonial sites in Virginia and Maryland.
Spears said the proposal fits with the National Park Service's vision to create "21st century parks" that combine natural and cultural resources, sometimes in several places, to tell a single story.
An example is the proposal for Harriet Tubman National Historical Park, he said.
One part would include sites on Maryland's Eastern Shore, where Tubman was born and spent 30 years as a slave before escaping in 1849. The other part would be in Auburn, N.Y., where she became part of the women's suffrage movement and helped elderly blacks.
The National Park Service studied the idea of a Delaware park in 2008, when the proposal included all of the New Castle and Lewes historic districts. The study concluded that a park could work here if it focused on the early Dutch and Swedish settlements in the 1600s and the period leading up to Delaware's ratification of the Constitution in 1787.
Critics balked at the scope of the proposal, which would have included private property and sites with little historic significance. The current proposal includes just six sites: Fort Christina and Holy Trinity (Old Swedes) Church in Wilmington; the Old New Castle Court House and Sheriff's House; the Green in Dover; John Dickinson Plantation southeast of Dover; and the Ryves Holt House in Lewes.
Creation of a national park would mean money to repair and maintain the sites, said Kim-Eric Williams, a professor of Swedish at the University of Pennsylvania and historian of the Swedish Colonial Society. Fort Christina State Park has been closed for repairs for several years, which Williams called "a national disgrace."
He said the designation could lead to an archaeological study to find the exact location of Fort Christina, which is now unknown.
The National Park Service uses several names to describe its sites, such as monument, memorial and recreation area. Carper's proposal would create the First State Heritage National Historical Park, putting it in the same family as Valley Forge National Historical Park. Several sites consist of separate places linked by a common name, similar to the park proposed for Delaware.
Colonial National Historical Park links the first British settlement of Jamestown, Va., and the British surrender site of Yorktown, Va. It bills itself as "the beginning and end of English Colonial America."
Klondike Gold Rush National Historical Park has sites in Alaska and Washington.
And Nez Perce National Historical Park is a collection of 38 sites spread over Idaho, Montana, Oregon and Washington to tell the story of the aboriginal Nez Perce people.
There's no shortage of proposals for national parks, Repanshek said.
Indeed, the House Committee on Natural Resources is now sifting through several proposals. One would commission a feasibility study of a park at Oak Point and North Brother Island in the Bronx, where a massive fire aboard the steamship General Slocum on June 15, 1904, killed more than 1,000 people and effectively wiped out a neighborhood of German immigrants.
Another bill would establish the Castle Nugent National Historic Site on St. Croix in the U.S. Virgin Islands to preserve "a Caribbean cultural landscape" of archaeological sites, a coral reef system and other natural features.
Carper expects Delaware's proposal to get support in the Senate. Sen. Mark Udall, D-Colo., co-sponsored Carper's bill in the last Congress and is now chairman of the Subcommittee on National Parks. Sen. Chris Coons, D-Del., is a member of the subcommittee and co-sponsor of Carper's bill.
Repanshek said he likes the idea of a Delaware park.
"It comes down to the history they're protecting and whether it's a good fit to the national park system," he said. "If we can have sites that address first ladies or steam locomotives or mammoth bones, why not?"