The United States has 63 national parks, which are Congressionally-designated protected areas operated by the National Park Service, an agency of the Department of the Interior.[1] National parks are designated for their natural beauty, unique geological features, diverse ecosystems, and recreational opportunities. While legislatively all units of the National Park System are considered equal with the same mission, national parks are generally larger and more of a destination, and hunting and extractive activities are prohibited.[2] National monuments, on the other hand, are also frequently protected for their historical or archaeological significance. Eight national parks (including six in Alaska) are paired with a national preserve, areas with different levels of protection that are administered together but considered separate units and whose areas are not included in the figures below. The 423 units of the National Park System can be broadly referred to as national parks, but most have other formal designations.[3]

A bill creating the first national park, Yellowstone, was signed into law by President Ulysses S. Grant in 1872, followed by Mackinac National Park in 1875 (decommissioned in 1895), and then Rock Creek Park (later merged into National Capital Parks), Sequoia and Yosemite in 1890. The Organic Act of 1916 created the National Park Service "to conserve the scenery and the natural and historic objects and wildlife therein, and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations."[4] Many current national parks had been previously protected as national monuments by the president under the Antiquities Act or as other designations created by Congress before being redesignated by Congress; the newest national park is New River Gorge, previously a National River, and the most recent entirely new park is National Park of American Samoa. A few former national parks are no longer designated as such, or have been disbanded. Fourteen national parks are designated UNESCO World Heritage Sites (WHS),[5] and 21 national parks are named UNESCO Biosphere Reserves (BR),[6] with eight national parks in both programs.

Thirty states have national parks, as do the territories of American Samoa and the U.S. Virgin Islands. The state with the most national parks is California with nine, followed by Alaska with eight, Utah with five, and Colorado with four. The largest national park is Wrangell–St. Elias in Alaska: at over 8 million acres (32,375 km2), it is larger than each of the nine smallest states. The next three largest parks are also in Alaska. The smallest park is Gateway Arch National Park, Missouri, at 192.83 acres (0.7804 km2). The total area protected by national parks is approximately 52.2 million acres (211,000 km2), for an average of 829 thousand acres (3,350 km2) but a median of only 208 thousand acres (840 km2).[7]

The national parks set a visitation record in 2017, with more than 84 million visitors and set a further record in 2018 with a 0.1% increase.[8][9] Great Smoky Mountains National Park in North Carolina and Tennessee has been the most-visited park since 1944,[10] and had over 14 million visitors in 2021.[11] In contrast, only about 7,000 people visited the remote Gates of the Arctic National Park and Preserve in Alaska in 2021.

The Pueblo Revival was inspired by the indigenous Pueblo people’s architecture in the Southwestern US. Pueblo homes were made of adobe or stucco and designed to handle the extreme temperatures of the desert.

Architects in California began to explore the Pueblo style in the late 19th century and the Pueblo Revival style spread across New Mexico, Arizona, and Colorado.

The Pueblo Revival hit its peak in the 1930s in Santa Fe, and these Pueblo-style elements are still popular in the Southwest:

• Rounded corners and irregular shapes
• Earth tones that reflect the desert colors
• Stepped effects with higher floors becoming smaller
• Flat roofs with parapet trim
• Exposed roof beams extending past the walls

The Pueblo Revival style is also commonly called Adobe or Santa Fe style architecture.

The Royal Exchange in London was founded in the 16th century by the merchant Sir Thomas Gresham on the suggestion of his factor Richard Clough to act as a centre of commerce for the City of London.[1] The site was provided by the City of London Corporation and the Worshipful Company of Mercers, who still jointly own the freehold. It is trapezoidal in shape and is flanked by Cornhill and Threadneedle Street, which converge at Bank junction in the heart of the city. It lies in the ward of Cornhill.

It has twice been destroyed by fire and subsequently rebuilt. The present building was designed by Sir William Tite in the 1840s. The site was notably occupied by the Lloyd's insurance market for nearly 150 years. Today the Royal Exchange contains Fortnum & Mason The Bar & Restaurant, luxury shops, and offices.

Traditionally, the steps of the Royal Exchange are the place where certain royal proclamations (such as the dissolution of parliament) are read out by either a herald or a crier. Following the death or abdication of a monarch and the confirmation of the next monarch's accession to the throne by the Accession Council, the Royal Exchange Building is one of the locations where a herald proclaims the new monarch's reign to the public.

Italianate architecture continues the trend of asymmetrical design, romanticism, and Medieval influence — this time borrowing features from Medieval Italy. Italianate style is common up and down the East Coast and peaked in popularity between 1850 and 1880.

Italianate architecture features:

• Belvederes for natural light and airflow
• Overhanging eaves with decorative support brackets
• Tall and narrow or pedimented windows with rounded crowns
• Cast iron detailing and decor

Pattern books were becoming a popular way for craftsmen to build homes in different styles. This flexibility meant Italianate features were accessible for a variety of homes including large estates and urban townhouses.

The French Colonial house style can be seen around the world and has significant variety among its sub-styles.

French Colonial houses have the same symmetry as other Colonial homes with these distinct features:

• Dormer windows, including one centered above the door
• External stairs to enter higher floors
• Iron stairs and balconies
• Slightly raised basements to support the floor

French Colonial houses are most similar to Spanish Colonial houses and easily identified by their elaborate iron balconies, stairs, and entrances.

The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the National Academy of Medicine (NAM).

As a national academy, new members of the organization are elected annually by current members, based on their distinguished and continuing achievements in original research. Election to the National Academy is one of the highest honors in the scientific field. Members of the National Academy of Sciences serve pro bono as "advisers to the nation" on science, engineering, and medicine. The group holds a congressional charter under Title 36 of the United States Code.

Founded in 1863 as a result of an Act of Congress that was approved by Abraham Lincoln, the NAS is charged with "providing independent, objective advice to the nation on matters related to science and technology. … to provide scientific advice to the government 'whenever called upon' by any government department."[2]

The Academy receives no compensation from the government for its services.[3]

The Academy currently has 2,984 members and international members. Existing members elect new members for life. Up to 120 members are elected every year; up to 30 foreign citizens may be elected as international members annually. The election process begins with a formal nomination, followed by a vetting period, and culminates in a final ballot at the Academy's annual meeting in April each year. Members are affiliated with a section -- a specific scientific field -- in one of six so-called "classes": (1) Physical and Mathematical Sciences; (2) Biological Sciences; (3) Engineering and Applied Sciences; (4) Biomedical Sciences; (5) Behavioral and Social Sciences; and (6) Applied Biological, Agricultural, and Environmental Sciences.[6] Since its founding, the Academy has elected 6,457 members. Harvard University is associated with the most members (329), some 5% of the all-time total. The top ten institutions, half of which are Ivy League universities, account for nearly 28% of all members ever elected.[11]