Bethesda, Maryland in the context of Maryland Route 355

Marriott Hotels & Resorts is Marriott International's brand of full-service hotels and resorts based in Bethesda, Maryland. As of June 30, 2020, there were 582 hotels and resorts with 205,053 rooms operating under the brand, in addition to 160 hotels with 47,765 rooms planned for development.

The National Institute on Aging (NIA) is a division of the U.S. National Institutes of Health (NIH), located in Bethesda, Maryland. The NIA itself is headquartered in Baltimore, Maryland.

The NIA leads a broad scientific effort to understand the nature of aging and to extend the healthy, active years of life. In 1974, under Public Law 93-296, Congress granted authority to form NIA to provide leadership in aging research, training, health information dissemination, and other programs relevant to aging and older people. In January 2011, President Obama signed into law the National Alzheimer’s Project Act, designating the NIA as the primary federal agency on Alzheimer's disease research.

Montgomery County is the most populous county in the U.S. state of Maryland. As of the 2020 United States census, the county's population was 1,062,061, increasing by 9.3% from 2010. The county seat is Rockville, while its most populous place is Germantown. The county is adjoined to Washington, D.C., the nation's capital, and is part of the Washington metropolitan area and the Washington–Baltimore combined statistical area. Most of the county's residents live in Silver Spring, Bethesda, Germantown, and the incorporated cities of Rockville and Gaithersburg.

The average household income in Montgomery County is the 20th-highest among U.S. counties as of 2020.

The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The NCBI is located in Bethesda, Maryland, and was founded in 1988 through legislation sponsored by US Congressman Claude Pepper.

The NCBI houses a series of databases relevant to biotechnology and biomedicine and is an important resource for bioinformatics tools and services. Major databases include GenBank for DNA sequences and PubMed, a bibliographic database for biomedical literature. Other databases include the NCBI Epigenomics database. All these databases are available online through the Entrez search engine. NCBI was directed by David Lipman, one of the original authors of the BLAST sequence alignment program and a widely respected figure in bioinformatics.

The National Institutes of Health (NIH) is the primary agency of the United States federal government responsible for biomedical and public health research. It was founded in 1887 and is part of the United States Department of Health and Human Services (HHS). Many NIH facilities are located in Bethesda, Maryland, and other nearby suburbs of the Washington metropolitan area, with other primary facilities in Research Triangle Park in North Carolina and smaller satellite facilities located around the United States.

The NIH conducts its scientific research through the NIH Intramural Research Program (IRP) and provides significant biomedical research funding to non-NIH research facilities through its Extramural Research Program. As of 2013, the IRP had 1,200 principal investigators and more than 4,000 postdoctoral fellows in basic, translational, and clinical research, being the largest biomedical research institution in the world, while, as of 2003, the extramural arm provided 28% of biomedical research funding spent annually in the U.S., or about US$26.4 billion. Basic research by the NIH contributed to every new drug approved by the Federal Drug Administration over the period 2010–2016.

Interstate 270 (I-270) is a 34.7-mile (55.8 km) auxiliary Interstate Highway in the U.S. state of Maryland that travels from I-495 (Capital Beltway) just north of Bethesda in Montgomery County north to I-70 in the city of Frederick in Frederick County. It consists of the 32.6-mile (52.5 km) mainline as well as a 2.1-mile (3.4 km) spur that provides access to and from southbound I-495. I-270 is known as the Washington National Pike, and makes up the easternmost stretch of the Dwight D. Eisenhower Highway. Most of the southern part of the route in Montgomery County passes through suburban areas around Rockville and Gaithersburg that are home to many biotech firms. This portion of I-270 is up to 12 lanes wide and consists of a local–express lane configuration as well as high-occupancy vehicle lanes (HOV lanes) that are in operation during peak travel times. North of the Gaithersburg area, the road continues through the northern part of Montgomery County, passing Germantown and Clarksburg as a six- to eight-lane highway with an HOV lane in the northbound direction only. North of here, I-270 continues through rural areas into Frederick County and toward the city of Frederick as a four-lane freeway.

The freeway was built between 1953 and 1960 as the Washington National Pike between Bethesda and Frederick and carried U.S. Route 240 (US 240), which was rerouted off what is now Maryland Route 355 (MD 355) between these two points. With the creation of the Interstate Highway System a few years later, the road was designated as I-70S along with US 240. There were plans to extend I-70S to I-95 in Washington, D.C., on the North Central Freeway from the Capital Beltway; however, they were canceled in the 1970s due to opposition from residents in the freeway's path. The concurrent US 240 designation was removed in 1972 and I-70S became I-270 in 1975. Increasing traffic levels led to a $200-million (equivalent to $509 million in 2024) widening of the road in Montgomery County to its current configuration. Many improvements are slated for I-270, including the widening of the route that would add high-occupancy toll lanes (HOT lanes).

Marriott International, Inc. is an American multinational company that operates, franchises, and licenses lodging brands that include hotel, residential, and timeshare properties. Marriott International owns over 37 hotel and timeshare brands with 9,000 locations and 1,597,380 rooms across its network (as of 2023). Marriott International is headquartered in Bethesda, Maryland. The company is the successor to the hospitality division of the Marriott Corporation, founded by J. Willard Marriott (1900–1985) and his wife Alice Marriott (1907–2000).

The United States National Library of Medicine (NLM), operated by the United States federal government, is the world's largest medical library.

Located in Bethesda, Maryland, the NLM is an institute within the National Institutes of Health. Its collections include more than seven million books, journals, technical reports, manuscripts, microfilms, photographs, and images on medicine and related sciences, including some of the world's oldest and rarest works.