Ohio History Connection
- Official OHS Website, formerly known as the Ohio Historical Society

Ohio History Central
- Online Encyclopedia of Ohio History

Cincinnati Museum Center
-Cincinnati Museum Center is a multi-museum complex housed in Union Terminal, an historic Art Deco train station and National Historic Landmark which includes the Cincinnati History Museum.

Historical Marker Database
- Online database of global historical markers and plaques

Remarkable Ohio
- Official Ohio Historical Marker database

- provides tools for you to catalog, mark and visit interesting and useful locations around the world

- Official Geocaching website. Players try to locate hidden containers, called geocaches, using a GPS-enabled device.

Exploring almost forgotten gravesites in Ohio
- Dedicated to cemetery preservation in the state of Ohio