Nathaniel H. Burt House

The Territory of Kansas was an organized incorporated territory of the United States that existed from May 30, 1854, until January 29, 1861, when the eastern portion of the territory was admitted to the Union as the free state of Kansas. The territory extended from the Missouri border west to the summit of the Rocky Mountains and from the 37th parallel north to the 40th parallel north. Originally part of Missouri Territory, it was unorganized from 1821 to 1854. Much of the eastern region of what is now the State of Colorado was part of Kansas Territory. The Territory of Colorado was created to govern this western region of the former Kansas Territory on February 28, 1861. The question of whether Kansas was to be a free or a slave state was, according to the Compromise of 1850 and the Kansas–Nebraska Act, to be decided by popular sovereignty, that is, by vote of the Kansans. The question of which Kansans were eligible to vote led to an armed-conflict period called Bleeding Kansas. Both pro-slavery and free-state partisans encouraged and sometimes financially supported emigration to Kansas, so as to influence the vote. During part of the territorial period there were two territorial legislatures, with two constitutions, meeting in two cities (one capital was burned by partisans of the other capital). Two applications for statehood, one free and one slave, were sent to the U.S. Congress. The departure of Southern legislators in January 1861 facilitated Kansas' entry as a free state, later the same month.

The Carnegie Arts Center of Leavenworth, Kansas an historic building in namesake city. It was originally the Leavenworth Public Library. Constructed in 1900 with funds donated by Andrew Carnegie, the two-story brick and limestone building was the first Carnegie Library in Kansas. The architect was Marshall R. Sanguinet of Fort Worth, Texas, who designed the Dallas Public Library at the same time. It is listed on the State and National Registers of Historic Places. From 1902 to 1987, the building housed the Leavenworth Public Library. From 1987 to 2012, the Carnegie Arts Center was housed in this building. It was a nonprofit organization which taught visual arts, painting, art history, music, dance, pottery and drama in the Leavenworth community for 25 years. In 2012 upon the disbanding of the nonprofit organization, ownership of the building was reverted to the city of Leavenworth, Kansas.

First Presbyterian Church, Leavenworth is a historic Presbyterian church at 407 Walnut Street in Leavenworth, Kansas. It was designed by architect William Pratt Feth and built in 1907–09.It was added to the National Register of Historic Places in 2006.It is a Classical Revival-style brick building, with brick laid in stretcher bond. It has an Ionic portico.

The AXA Building, at 205 S. 5th St. in Leavenworth, Kansas, was built in 1905. It was listed on the National Register of Historic Places in 1972.It is an ornate and two-and-a-half story red brick commercial building, with a 125 feet (38 m) facade along Fifth Street.It was designed by Leavenworth architect William B. Feth and built by contractor R. B. Yoakum. Known originally as the Eppenscheid Building. it was built for Charles Espenscheid, a St. Louis investor.It is Late Victorian in style.According to a guide to Kansas architecture, the building "stands out among its neighbors because of the inventiveness of its highly articulated Neo-classical ornament, particularly along the cornice, at its second-story bay windows, and around the lobby entry."

The C.W. Parker Carousel Museum, also known as the Leavenworth Carousel Museum, is located in Leavenworth, Kansas and is one of several museums sponsored by the Leavenworth Historical Museum Association. Opened in 2005, the building houses carousels that are historically registered, as well as a C.W. Parker cylinder piano, an Artizan A-X-1 band organ, and a Wurlitzer 153 Band Organ. It also has several reproduced or repaired carousel horses. Charles Wallace Parker (C. W. Parker) manufactured the first Carry-Us-All amusement ride in 1898. This invention was such a success that his quickly growing company in Abilene, Kansas was moved to Leavenworth. The Carousel Museum is a non-profit organization that operates through community donations and volunteer efforts.

Immaculata High School was a private, Roman Catholic high school in Leavenworth, Kansas, United States. It was located in the Roman Catholic Archdiocese of Kansas City in Kansas.

Leavenworth USD 453 is a public unified school district headquartered in Leavenworth, Kansas, United States.

Leavenworth Riverfront Community Center was a former Union Pacific railroad station located in Leavenworth, Kansas, United States. It is also known as the Old Union Depot when it was listed on the National Register of Historic Places (NRHP) in 1987. It is currently known as the Leavenworth Riverfront Community Center.

The Terminal Bridge was a pontoon bridge and then a through-truss swing bridge at Leavenworth, Kansas. The pontoon bridge opened in 1889. The steel truss bridge opened on January 2, 1894, and was demolished in 1987.

Leavenworth () is the county seat and largest city of Leavenworth County, Kansas, United States and is part of the Kansas City metropolitan area. As of the 2020 census, the population of the city was 37,351. It is located on the west bank of the Missouri River. The site of Fort Leavenworth, built in 1827, the city became known in American history for its role as a key supply base in the settlement of the American West. During the American Civil War, many volunteers joined the Union Army from Leavenworth. The city has been notable as the location of several prisons, particularly the United States Disciplinary Barracks and United States Penitentiary, Leavenworth.

The Richard Allen Cultural Center opened in 1992 to highlight African-American history in Leavenworth, Kansas. In 1992, the museum opened in the former home of U.S. Army Captain William Bly, a Buffalo Soldier during World War I. The home is decorated to look as it would have in the early 1900s. In 2002, an addition was built to the front of the original home to display more items teaching about African-American history in Kansas. One display includes prints of original photographic plate negatives donated to the museum, called the Black Dignity Photos from the Mary Everhard collection. The photographs are African-American pioneers who lived in and around the Leavenworth area from 1870s to 1920s. Other items include military artifacts from African-American soldiers who served on Fort Leavenworth, including Colin Powell. The Richard Allen Cultural Center also contains a Ku Klux Klan costume and photographs depicting KKK activities in Leavenworth. One artifact is a news article discussing the public lynching of an African-American citizen of Leavenworth, Fred Alexander. The Richard Allen Cultural Center seeks to preserve these pieces of Leavenworth, Kansas history so that they are not forgotten. In 2016 a bronze bust of Cathay Williams, featuring information about her and with a small rose garden around it, was unveiled outside the Richard Allen Cultural Center.

The Centennial Bridge is a through arch bridge road bridge over the Missouri River connecting Leavenworth, Kansas, and Platte County, Missouri. Constructed in 1955, it was initially a toll bridge. The bridge opened in 1955, a year after Leavenworth celebrated its centennial as the first city incorporated in Kansas. It is a two-span arch bridge connecting K-92 and Missouri Route 92. Its main span is 419.8 feet, and its total length is 2,571.2 feet. During the construction a spur of Route 45 called the "Leavenworth cutoff" was built to speed traffic to Kansas City, Missouri. The two-mile spur, even though it is in Missouri, was maintained by the city of Leavenworth until the tolls were removed from the Centennial Bridge in May 1977. The bridge is now maintained by the Kansas Department of Transportation.