Census-Online.com - census transcriptions for Delaware Co.
Delaware County GenWeb Project collection of online resources for genealogy researchers
Delaware County Message Board read and post messages with other genealogy researchers of this county
Delaware County, PA Genealogy Forum read and post messages about your ancestors for this county
Genealogy Trails - Delaware County
Interment.net - cemeteries of  Delaware Co.
Ridley Township History
The Tombstone Transcription Project - cemeteries for Delaware Co; PA
US GenWeb Archives for Delaware County cemeteries, newspapers, wills, military rosters etc recorded online here
1790 Federal Census, Delaware County, Pennsylvania

Additional Resources

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