26 miles east of Los Angeles, in Los Angeles County, California, lies the city of Glendora in the San Gabriel Valley. Situated between the South Hills to the south and the San Gabriel Mountains range to the north, the city is situated at the easternmost point of the San Gabriel Valley. The city is 19.6 square miles in total, of which 19.4 square miles are land and 0.2 square miles, or 0.84%, are water, according to the US Census Bureau.

In contrast to coastal California, Glendora has a dry Mediterranean climate (Köppen Csa), with hotter summers and somewhat colder winters. The winter months provide a rainy season, although the most of the year is marked by dry weather. Hot summers and fall Santa Ana winds, which affect the neighboring mountains, make the city more vulnerable to flames. Wildfires that have recently damaged Glendora and the surrounding areas include the 2009 Morris Fire and the 2015 Cabin Fire. February's high temperature is often 68°F (20°C), while August's high temperature is typically 92°F (33°C). January's low temperature is typically 43°F (6°C), while August's low temperature is 43°F (17°C). There is 18.16 inches (461 mm) of precipitation on average per year.

Two highly regarded public school districts, Glendora Unified and Charter Oak Unified School Districts, which routinely rank among the best in the state and nation, serve Glendora. Schools in these districts have earned recognition as Gold Ribbon and California Distinguished Schools. The elementary schools are Willow (COUSD), Cullen, La Fetra, Sellers, Stanton, Sutherland, and Washington (COUSD). Middle schools in the COUSD are Goddard, Sandburg, and Royal Oak. For high school education, there is Glendora High School, Arrow Continuation High School (COUSD), and Whitcomb Continuation High School. Private educational institutions that provide a variety of educational opportunities include Hope Lutheran Church and School, Foothill Christian School, St. Lucy's Priory High School, and St. Dorothy School. In the city, Citrus College functions as a higher education establishment.

Glendora is home to several notable cultural institutions, including the Haugh Performing Arts Center, Glendora Public Library, Glendora Public Market, and the Glendora Historical Society Museum, designed by Michael Rubel. With parks, trails, and a variety of programs, the city is proud of its wide range of recreational options. Among the notable outdoor areas are the Louie Pompei Memorial Sports Park, Finkbiner Park, Big Tree Park, which features a 140-year-old Moreton Bay Fig tree, Centennial Heritage Park, which depicts a citrus ranch from the late 19th to early 20th century, South Hills Park and wilderness trail, Colby Trail, and Mystic Canyon Trail. Renowned for their picturesque routes through the San Gabriel Mountains, Glendora Mountain Road and Glendora Ridge Road are popular destinations for cyclists and tourists. In addition, they have played host to stages of the worldwide Tour of California.

Two of Glendora's transportation choices are the Metro A Line termini station in Azusa, which connects to the larger Metro system, and Foothill Transit, which offers both local and express service. There are plans to extend the A Line to Montclair in the future, with a Glendora station opening in 2026. During the week, Glendora Mini Bus offers a shuttle service to the APU/Citrus College Metro station, the Metrolink Commuter Rail Station in Covina, and inter-school connections. Glendora's location near the intersection of the 210 and 57 major freeways, as well as the Historic U.S. Route 66, guarantees easy access to Southern California. Despite not having an airport inside its boundaries, Glendora is 45 miles away from several major airports, including as LAX, BUR, ONT, LGB, and SNA.