Cities and Towns in DeKalb County, Illinois

Founded in 1837, DeKalb County is one of 102 counties in the state of Illinois. Historically, DeKalb County was formed from Kane County. The city of Sycamore is the county seat. With FIPS code of 37, DeKalb County has a population of 100,414 and area of 631 square miles (1,634 km²).

List of all cities in DeKalb County, IL alphabetically

City/Town Postal Code Area Code
Clare, IL 60111 815/779
Cortland, IL 60112 815/779
Dekalb, IL 60115 815/779
Esmond, IL 60129 815/779
Fairdale, IL 60146 815/779
Genoa, IL 60135 815/779
Herbert, IL 60145 815/779
Hinckley, IL 60520 815/779
Kingston, IL 60145 815/779
Kirkland, IL 60146 815/779
Malta, IL 60150 815/779
McGirr, IL 60556 815/779
Sandwich, IL 60548 815/779
Shabbona, IL 60550 815/779
Somonauk, IL 60552 815/779
Sycamore, IL 60178 815/779
Valley View, IL 60145 815/779
Waterman, IL 60556 815/779

Major Cities and Towns in DeKalb County, Illinois

DeKalb

Area, Population, and Zip Codes

  • Area: 14.81 square miles
  • Population: 43,093 (2023 estimate)
  • Zip Codes: 60115
  • Latitude: 41.9295° N
  • Longitude: 88.7504° W

Location and History

DeKalb, the largest city in DeKalb County, is located about 60 miles west of Chicago along Interstate 88. Founded in 1856 and named after Johann de Kalb, a German hero of the American Revolutionary War, DeKalb quickly became an important center for agriculture, particularly corn production. The city’s economy flourished in the late 19th century with the invention of barbed wire by Joseph Glidden, a DeKalb native, which revolutionized farming across the Midwest. DeKalb is also home to Northern Illinois University (NIU), founded in 1895, which has played a significant role in the city’s growth and development.

Major Schools and Landmarks

DeKalb is served by DeKalb Community Unit School District 428, with DeKalb High School being its main high school. As the home of Northern Illinois University, DeKalb boasts the NIU Huskie Stadium, which hosts football games and other major events. The Ellwood House Museum, a stately Victorian mansion once owned by barbed wire magnate Isaac Ellwood, is a major historical landmark. DeKalb’s Egyptian Theatre, a beautifully restored 1920s movie palace, hosts live performances, concerts, and film screenings, contributing to the city’s vibrant cultural scene.


Sycamore

Area, Population, and Zip Codes

  • Area: 10.16 square miles
  • Population: 18,922 (2023 estimate)
  • Zip Codes: 60178
  • Latitude: 41.9884° N
  • Longitude: 88.6861° W

Location and History

Sycamore, the county seat of DeKalb County, is located approximately 5 miles northeast of DeKalb along Illinois Route 64. The city was first settled in 1835, with its name inspired by the large sycamore trees in the area. Sycamore grew steadily throughout the 19th century as a center for agriculture and trade. The arrival of the railroad in the 1850s helped solidify Sycamore’s role as a regional hub for farmers and merchants. The historic courthouse, built in 1905, remains a central part of the city’s downtown, symbolizing Sycamore’s role as the political and cultural heart of DeKalb County.

Major Schools and Landmarks

Sycamore is served by Sycamore Community Unit School District 427, with Sycamore High School being the primary educational institution. Notable landmarks include the DeKalb County Courthouse, a grand Beaux-Arts style building, and the Sycamore History Museum, which showcases the city’s rich heritage. The Midwest Museum of Natural History is another significant attraction, offering educational exhibits on natural science and wildlife. Sycamore hosts the annual Pumpkin Festival, a popular community event that draws visitors from across the region for its parade, carnival, and arts and crafts fair.


Genoa

Area, Population, and Zip Codes

  • Area: 2.47 square miles
  • Population: 5,306 (2023 estimate)
  • Zip Codes: 60135
  • Latitude: 42.0978° N
  • Longitude: 88.6920° W

Location and History

Genoa is located in the northern part of DeKalb County, along the Kishwaukee River, approximately 15 miles north of DeKalb. The town was established in 1835 by Thomas Madison, and it was named after Genoa, New York, which was his hometown. Early settlers in Genoa were primarily farmers, and the arrival of the railroad in the 1850s allowed the town to expand as a grain-shipping point. Genoa has maintained its rural character over the years while also attracting new residents due to its proximity to larger cities like Rockford and DeKalb.

Major Schools and Landmarks

Genoa is part of Genoa-Kingston Community Unit School District 424, with Genoa-Kingston High School serving the local student population. Major landmarks in the town include the Kishwaukee River itself, which provides opportunities for fishing, kayaking, and hiking along its scenic banks. Chamberlain Park is a popular local spot for recreational activities, featuring sports fields, playgrounds, and a swimming pool. The Genoa Veterans Home Museum honors the town’s military history and serves as a cultural hub for the community. Genoa also hosts the annual Genoa Days festival, celebrating the town’s history and community spirit.


Sandwich

Area, Population, and Zip Codes

  • Area: 4.71 square miles
  • Population: 7,421 (2023 estimate)
  • Zip Codes: 60548
  • Latitude: 41.6545° N
  • Longitude: 88.6217° W

Location and History

Sandwich is located in the southwestern part of DeKalb County, though it also extends into Kendall and LaSalle counties. The town was founded in 1855 and was named by Almon Gage, a state legislator from Sandwich, New Hampshire. With the arrival of the railroad, Sandwich quickly grew as an agricultural and industrial hub. The town became famous for its annual Sandwich Fair, which started in 1888 and is one of the oldest and largest county fairs in Illinois. Today, Sandwich continues to attract visitors and residents for its historical charm and vibrant community events.

Major Schools and Landmarks

Sandwich is served by Sandwich Community Unit School District 430, with Sandwich High School being the main educational institution. The town’s most famous landmark is the Sandwich Fairgrounds, home to the annual Sandwich Fair, which features agricultural exhibits, carnival rides, and entertainment. The Stone Mill Museum is another notable site, showcasing the town’s history and its early industries. Harvey Creek Conservation Area provides outdoor recreational opportunities, including hiking and birdwatching, further enhancing Sandwich’s appeal as a welcoming and scenic community.


Hinckley

Area, Population, and Zip Codes

  • Area: 1.23 square miles
  • Population: 2,049 (2023 estimate)
  • Zip Codes: 60520
  • Latitude: 41.7689° N
  • Longitude: 88.6396° W

Location and History

Hinckley is located in the southwestern part of DeKalb County, approximately 20 miles southwest of DeKalb along U.S. Route 30. Established in 1875, the town grew rapidly with the construction of the Chicago and Iowa Railroad, which facilitated trade and commerce in the area. Hinckley is perhaps best known for hosting the first-ever Harlem Globetrotters game in 1927, an event that is celebrated as a significant part of the town’s cultural heritage. Over the years, Hinckley has remained a small but vibrant community, maintaining its agricultural roots while welcoming new businesses and residents.

Major Schools and Landmarks

Hinckley is part of Hinckley-Big Rock Community Unit School District 429, with Hinckley-Big Rock High School serving local students. One of the key landmarks in Hinckley is Pioneer Park, which features sports fields, picnic areas, and playgrounds, making it a hub for family activities. The town also celebrates its connection to basketball history with the Hinckley Historical Society Museum, which documents the first Harlem Globetrotters game. The annual Hinckley Fireworks Festival is a major community event, attracting visitors from across the county to enjoy live music, food, and fireworks.


Cortland

Area, Population, and Zip Codes

  • Area: 2.45 square miles
  • Population: 4,503 (2023 estimate)
  • Zip Codes: 60112
  • Latitude: 41.9228° N
  • Longitude: 88.6845° W

Location and History

Cortland is located just east of DeKalb along Illinois Route 38. Founded in the mid-19th century, the town initially grew as a small farming community. Its location along major transportation routes helped Cortland develop into a regional hub for agriculture. Over the years, the town has expanded, and its proximity to larger cities like DeKalb and Sycamore has made it an attractive location for new housing developments. Cortland is one of the fastest-growing towns in DeKalb County, balancing its rural charm with modern amenities.

Major Schools and Landmarks

Cortland is served by DeKalb Community Unit School District 428, with students typically attending schools in nearby DeKalb. Major landmarks in Cortland include Houtz Park, which provides playgrounds, sports fields, and walking trails for residents to enjoy. The Cortland Community Library is another important cultural institution, offering a range of educational programs and events. The town hosts an annual Cortland Summer Fest, which includes live music, carnival rides, and a parade, bringing together the community to celebrate its heritage and growth.