| Opdyke, Illinois | |
| Settlement Type: | Census-designated place |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Illinois |
| Subdivision Type2: | County |
| Subdivision Name2: | Jefferson |
| Subdivision Type3: | Township |
| Subdivision Name3: | Pendleton |
| Pushpin Map: | Illinois |
| Pushpin Map Caption: | Location of Opdyke within Illinois |
| Coordinates: | 38.2583°N -88.7897°W |
| Area Footnotes: | [1] |
| Area Total Km2: | 1.37 |
| Area Total Sq Mi: | 0.53 |
| Area Land Sq Mi: | 0.53 |
| Area Water Sq Mi: | 0.00 |
| Elevation Ft: | 515 |
| Population As Of: | 2020 |
| Population Total: | 236 |
| Population Density Km2: | 172.54 |
| Population Density Sq Mi: | 446.97 |
| Timezone1: | CST |
| Utc Offset1: | -6 |
| Timezone1 Dst: | CDT |
| Utc Offset1 Dst: | -5 |
| Postal Code Type: | Postal code |
| Postal Code: | 62872 |
| Area Code: | 618 |
| Blank Name: | FIPS code |
| Blank Info: | 17-56198 |
| Blank1 Name: | GNIS ID |
| Blank1 Info: | 2628558 |
| Unit Pref: | Imperial |
| Area Land Km2: | 1.37 |
| Area Water Km2: | 0.00 |
Opdyke is a census-designated place in the southeastern part of Jefferson County, Illinois, United States. As of the 2010 census, its population was 254.[2]
Opdyke was laid out in 1871, following construction of the St. Louis & Southeastern Railroad. The nearby, earlier town of Lynchburg was largely abandoned and moved to Opdyke.
A part of the railroad investment in this area was funded by a mortgage of $4,525,000 by Calhoun & Opdyke of New York. The town is named for Opdyke. It is possible that the name of the village is all that they got out of the investment.
The original surveys of Illinois, made around 1800, show the Goshen Road passing through what is now the center of Opdyke in a north/south direction. The road was about a quarter mile east of the north/south section road that now forms the western boundary of the village. Few traces of this road now remain, and it is not clear if the road was still present at the time of the founding of the village.
Opdyke formed as a village alongside the railroad tracks. The railroad is no longer a significant factor in the existence of the village, which now fronts on Illinois Route 142. Interstate 64 passes a mile north of the village, without an interchange.