Rides and other cycling information:

Weekly Rides The go-to site for rides and events in and around Charlotte and the Carolinas.
Road Bike Rider: Information and articles for recreational cyclists
Rock Hill Parks, Recreation and Tourism:  Schedule and information for Rock Hills cycling facilities.
Visit York County - Biking: Descriptions of the York County bike routes

Cycling Advocacy:

Palmetto Cycling Coalition Works towards making South Carolina bicycle and pedestrian friendly.
Bike Law: How to ride safely and what to do in case of an accident.
Bike/Ped Coalition of York County: Supports York County becoming more bicycle and pedestrian friendly.

Cycling Clubs:

Aiken Bicycle Club
Freewheelers of Spartanburg
Gaston County Cyclists
Greenville Spinners
Mooresville Area Cyclists

Interesting Articles:

Great article on Group Rides by BikeLaw:  Read the Article
Are Bike Helmets Worth It?  The Dangers of Riding Without a Helmet