Question: What service maintains the collection of historical records for Yellowstone and the National Park Service?
About the article "Yellowstone National Park", section "Heritage and Research Center".

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The Heritage and Research Center is located at Gardiner, Montana, near the north entrance to the park.
The center is home to the Yellowstone National Park's museum collection, archives, research library, historian, archeology lab, and herbarium.
The Yellowstone National Park Archives maintain collections of historical records of Yellowstone and the National Park Service.
The collection includes the administrative records of Yellowstone, as well as resource management records, records from major projects, and donated manuscripts and personal papers.
The archives are affiliated with the National Archives and Records Administration.
 "Field key to the flora of Yellowstone National Park, WY".
1975, Yellowstone National Park: Yellowstone Library and Museum Association.
"Fire as an ecological force in Yellowstone ecosystems" (Information paper / Yellowstone National Park) "Yellowstone vegetation: consequences of environment and history in a natural setting", 1990.
Boulder, CO: Roberts Rinehart, Inc. "Plants and their environments: Proceedings of the first biennial scientific conference on the Greater Yellowstone Ecosystem", 1994.
Denver, CO: National Park Service.  
Yellowstone Airport is a state-owned public-use airport located one nautical mile (2 km) north of the central business district of West Yellowstone, a town in Gallatin County, Montana, United States.
Although only open from June through September, commercial service is available during those months.
Scheduled airline service is subsidized by the Essential Air Service program.
As per Federal Aviation Administration records, the airport had 4,186 passenger boardings (enplanements) in calendar year 2008, 4,331 enplanements in 2009, and 4,451 in 2010.
It is included in the National Plan of Integrated Airport Systems for 2011–2015, which categorized it as a "non-primary commercial service" airport (between 2,500 and 10,000 enplanements per year).
The town of West Yellowstone is located at the west entrance to Yellowstone National Park.
The airport should not be confused with Yellowstone Regional Airport in Cody, Wyoming, which is 104 miles (167 km) from this airport and about from the east entrance of Yellowstone National Park. 
Yellowstone ranks among the most popular national parks in the United States.
Since the mid-1960s, at least 2 million tourists have visited the park almost every year.
In 2010, a record number of visitors came to the park in July: 975,000.
July is the busiest month for Yellowstone National Park.
At peak summer levels, 3,700 employees work for Yellowstone National Park concessionaires.
Concessionaires manage nine hotels and lodges, with a total of 2,238 hotel rooms and cabins available.
They also oversee gas stations, stores and most of the campgrounds.
Another 800 employees work either permanently or seasonally for the National Park Service.
Park service roads lead to major features; however, road reconstruction has produced temporary road closures.
Yellowstone is in the midst of a long term road reconstruction effort, which is hampered by a short repair season.
In the winter, all roads aside from the one which enters from Gardiner, Montana, and extends to Cooke City, Montana, are closed to wheeled vehicles.
Park roads are closed to wheeled vehicles from early November to mid April, but some park roads remain closed until mid-May.
The park has of paved roads which can be accessed from five different entrances.
There is no public transportation available inside the park, but several tour companies can be contacted for guided motorized transport.
In the winter, concessionaires operate guided snowmobile and snow coach tours, though their numbers and access are based on quotas established by the National Park Service.
Facilities in the Old Faithful, Canyon and Mammoth Hot Springs areas of the park are very busy during the summer months.
Traffic jams created by road construction or by people observing wildlife can result in long delays.
The National Park Service maintains 9 visitor centers and museums and is responsible for maintenance of historical structures and many of the other 2,000 buildings.
These structures include National Historical Landmarks such as the Old Faithful Inn built from 1903 to 1904 and the entire Fort Yellowstone – Mammoth Hot Springs Historic District.
An historical and educational tour is available at Fort Yellowstone which details the history of the National Park Service and the development of the park.
Campfire programs, guided walks and other interpretive presentations are available at numerous locations in the summer, and on a limited basis during other seasons.
Camping is available at a dozen campgrounds with more than 2,000 campsites.
Camping is also available in surrounding National Forests, as well as in Grand Teton National Park to the south.
Backcountry campsites are accessible only by foot or by horseback and require a permit.
There are of hiking trails available.
The park is not considered to be a good destination for mountaineering because of the instability of volcanic rock which predominates.
Visitors with pets are required to keep them on a leash at all times and are limited to areas near roadways and in "frontcountry" zones such as drive in campgrounds.
Around thermal features, wooden and paved trails have been constructed to ensure visitor safety, and most of these areas are handicapped accessible.
The National Park Service maintains a year round clinic at Mammoth Hot Springs and provides emergency services throughout the year.
Hunting is not permitted, though it is allowed in the surrounding national forests during open season.
Fishing is a popular activity, and a Yellowstone Park fishing license is required to fish in park waters.
Many park waters are fly fishing only and all native fish species are catch and release only.
Boating is prohibited on rivers and creeks except for a stretch of the Lewis River between Lewis and Shoshone Lake, and it is open to non-motorized use only.
Yellowstone Lake has a marina, and the lake is the most popular boating destination.
In the early history of the park, visitors were allowed, and sometimes even encouraged, to feed the bears.
Visitors welcomed the chance to get their pictures taken with the bears, who had learned to beg for food.
This led to numerous injuries to humans each year.
In 1970, park officials changed their policy and started a vigorous program to educate the public on the dangers of close contact with bears, and to try to eliminate opportunities for bears to find food in campgrounds and trash collection areas.
Although it has become more difficult to observe bears in recent years, the number of human injuries and deaths has taken a significant drop and visitors are in less danger.
The seventh recorded bear-related death in the park's history occurred in August 2011.
Other protected lands in the region include Caribou-Targhee, Gallatin, Custer, Shoshone and Bridger-Teton National Forests.
The National Park Service's John D. Rockefeller, Jr. Memorial Parkway is to the south and leads to Grand Teton National Park.
The famed Beartooth Highway provides access from the northeast and has spectacular high altitude scenery.
Nearby communities include West Yellowstone, Montana; Cody, Wyoming; Red Lodge, Montana; Ashton, Idaho; and Gardiner, Montana.
The closest air transport is available by way of Bozeman, Montana; Billings, Montana; Jackson; Cody, Wyoming, or Idaho Falls, Idaho.
Salt Lake City, to the south, is the closest large metropolitan area. 
 Fishing Bridge Museum (1929), Yellowstone National Park (designed by NPS architect Herbert Maier), part of the Norris, Madison, and Fishing Bridge Museums which has been designated as a National Historic Landmark Grand Loop Road Historic District, Grand Loop Rd.
Yellowstone National Park, Wyoming (National Park Service), NRHP-listed Lamar Buffalo Ranch, E of Mammoth Hot Springs on Northeast Entrance Rd.
Mammoth Hot Springs, Wyoming (National Park Service), NRHP-listed Madison Museum (1929), Yellowstone National Park (designed by NPS architect Herbert Maier), part of the Norris, Madison, and Fishing Bridge Museums which has been designated as a National Historic Landmark Norris Geyser Basin Museum (1929-1930), Yellowstone National Park (designed by NPS architect Herbert Maier), part of the Norris, Madison, and Fishing Bridge Museums which has been designated as a National Historic Landmark Northeast Entrance Station, US 212, Yellowstone National Park, Montana (NPS Branch of Plans & Design), NRHP-listed Obsidian Cliff Kiosk (1931), Yellowstone National Park Mammoth, Wyoming (designed by NPS park naturalist, Carl Russell), NRHP-listed :First "wayside exhibit built in the National Park System", an "open air museum-in-miniature", and a small shelter for interpretative information, in National Park Service Rustic style.
Old Faithful Museum of Thermal Activity (1929), Yellowstone National Park (designed by NPS architect Herbert Maier), demolished in 1971