Welcome to Seneca ...

The village of Seneca is primarily located in La Salle County<1>. A portion of Seneca extends into Grundy County.

The location of Seneca has been provided by the Geographic Names Information System (ie- the GNIS).<2>

While we don't have a date for the founding of Seneca, you might consider that their post office opened  in 1865.

The village was incorporated in 1858.

From the  Census Estimates for 2019, Seneca has a population of 2,241 people<3> (see below for details).

Seneca is 510 feet [155 m] above sea level.<4>.

Time Zone: Seneca lies in the Central Time Zone (CST/CDT) and observes daylight saving time

Area codes for Seneca: (815) & (779)<5>

The ZIP code for Seneca: 61360<6>

The village of Seneca has also been called Crotty. and Seneca village. For more information about the names of Seneca, see The Names of Seneca on our Genealogy Page.

Population Details ...

Taken from the 2019 Census Estimates, Seneca had an population of 2,241 people. This is a decrease of 5.48% since the 2010 Census (or an increase of 9.16% since the 2000 Census).

At the time of the 2010 Census, Seneca had a population of 2,371 people. This makes Seneca the county's 8th most populous community.

The population of Seneca represents 0.02% of the total population of Illinois (which has 12,830,632 people), making it the state's 459th most populous community.

With a 2010 count of 2,371 people, the population of Seneca increased 15.49% from the 2000 Census (which had a count of 2,053 people).

More information can be found on the Census Page for Seneca.

Communities Also Named Seneca ...

Using our Gazetteer, we found that there are 26 communities that are also named Seneca - they are located in Arizona, California, Florida (2), Iowa, Kansas, Maryland, Michigan (2), Mississippi, Missouri, Nebraska, New Mexico, New York, Ohio (2), Ontario, Oregon (2), Pennsylvania, South Carolina, South Dakota, Texas, Virginia, West Virginia and Wisconsin.

For more information, see our Tidbits & Trivia Page for Seneca.

Communities near Seneca ...

We have created a list of 10 communities that are near Seneca.

• Ottawa
  (12 miles [19.3 km] to the west)
  • Jump to our Gazetteer entry for Ottawa
  • Ottawa is located in La Salle County
  • Population from the 2020 Census: 18,097 people
  • Jump to TripAdvisor's Tourism page for Ottawa <7>
• Morris
  (10 miles [16.1 km] to the northeast)
  • Note: The GPS coordinates that we are using for Morris have been provided by the GNIS.<2> The coordinates still need to be verified.
  • Jump to our Gazetteer entry for Morris
  • Morris is located in Grundy County
  • Population from the 2020 Census: 15,162 people
  • Jump to TripAdvisor's Tourism page for Morris <7>
• Channahon
  (19 miles [30.6 km] to the northeast)
  • Note: The GPS coordinates that we are using for Channahon have been provided by the GNIS.<2> The coordinates still need to be verified.
  • Jump to our Gazetteer entry for Channahon
  • Channahon is located in Grundy County
  • Population from the 2020 Census: 13,409 people
  • Jump to TripAdvisor's Tourism page for Channahon <7>
• Streator
  (17 miles [27.4 km] to the southwest)
  • Jump to our Gazetteer entry for Streator
  • Streator is located in La Salle County
  • Population from the 2020 Census: 12,933 people
  • Jump to TripAdvisor's Tourism page for Streator <7>
• Minooka
  (19 miles [30.6 km] to the northeast)
  • Note: The GPS coordinates that we are using for Minooka have been provided by the GNIS.<2> The coordinates still need to be verified.
  • Jump to our Gazetteer entry for Minooka
  • Minooka is located in Grundy County
  • Population from the 2020 Census: 11,456 people
  • Jump to TripAdvisor's Tourism page for Minooka <7>
• Coal City
  (17 miles [27.4 km] to the east)
  • Note: The GPS coordinates that we are using for Coal City have been provided by the GNIS.<2> The coordinates still need to be verified.
  • Jump to our Gazetteer entry for Coal City
  • Coal City is located in Grundy County
  • Population from the 2020 Census: 5,351 people
  • Jump to TripAdvisor's Tourism page for Coal City <7>
• Dwight
  (17 miles [27.4 km] to the southeast)
  • Jump to our Gazetteer entry for Dwight
  • Dwight is located in Livingston County
  • Population from the 2020 Census: 3,984 people
  • Jump to TripAdvisor's Tourism page for Dwight <7>
• Sheridan
  (15 miles [24.1 km] to the north)
  • Note: The GPS coordinates that we are using for Sheridan have been provided by the GNIS.<2> The coordinates still need to be verified.
  • Jump to our Gazetteer entry for Sheridan
  • Sheridan is located in La Salle County
  • Population from the 2020 Census: 2,515 people
  • Jump to TripAdvisor's Tourism page for Sheridan <7>
• Diamond
  (18 miles [29 km] to the east)
  • Jump to our Gazetteer entry for Diamond
  • Diamond is located in Grundy County
  • Population from the 2020 Census: 2,484 people
  • Jump to TripAdvisor's Tourism page for Diamond <7>
• Gardner
  (17 miles [27.4 km] to the southeast)
  • Note: The GPS coordinates that we are using for Gardner have been provided by the GNIS.<2> The coordinates still need to be verified.
  • Jump to our Gazetteer entry for Gardner
  • Gardner is located in Grundy County
  • Population from the 2020 Census: 1,377 people
  • Jump to TripAdvisor's Tourism page for Gardner <7>

To Help With Your Genealogy Research ...

We have a couple of sections for those tracing their genealogy.

We created a list of cemeteries that are in the area around Seneca. Our list includes the location of those cemeteries and we provide an overhead view. See our Cemetery List for Seneca.

Using the information from an 1895 Atlas, we've created a list of communities that were in the area of Seneca. Our list includes information such as whether the 1895 community had a post office or railroad service. See our List of 1890's Communities around Seneca.

We also have a detailed list of newspapers that have been published in the area around Seneca. See our Newspapers Page for Seneca.

TripAdvisor Tourism Pages for Seneca ...

Looking for more information about Seneca? A wonderful source is the TripAdvisor website. We always start with the TripAdvisor Tourism page, where you can read an overview with links that will help you find lodging, restaurants and attractions.

In addition to the Tourism page for Seneca, there are neighboring communities that also have Tourism pages. More information about those communities can be found on our TripAdvisor Page for Seneca.

Adding Seneca to Our Gazetteer ...

We originally found mention of Seneca in both the FIPS-55 and the GNIS. For more information, see the FIPS and GNIS Codes sections on our Miscellaneous Page.

From our notes, the earliest published mention we've found for Seneca was in the document titled List of Post Offices from Cameron Blevins and Richard Helbock.<8>

From that list, the Seneca post office opened in 1865.

We also found Seneca in the book titled List of Post Offices in the United States (1870).

For more details, see References and Mentions for Seneca.

Off-the-Road Links ...

Unfortunately, we don't know of a website for Seneca. If you can help, please contact us through our Feedback Page.

The official website for La Salle County: www.lasallecounty.org/

The official website for State of Illinois: https://illinois.gov