• Armed Settlers of Catan - A variant with military rules.
• BoardGameGeek - Offers file downloads and reviews.
• Constructing a 3D Settlers of Catan Board - Article describing using silicone molds and resin pieces to create a hand-crafted board with a three-dimensional appearance.
• Die Siedler von Catan - English rules translation, English cheat sheets for German editions of the basic game, Seafarers, Cities and Knights and 5/6 player expansion. Variants, map pictures and scenario information for expansions.
• KMWs Spielplatz - Description, review, pictures and diagrams of the Seafarers of Catan expansion and how to setup Poor man's Seafaring expansion. [English pages on a German site]
• Kulkmann's Gamebox - Descriptions and reviews of Settlers, Seafarers, "Stadte und Ritter" (Cities and Knights) and the Historical Scenarios (Alexander and Cheops).
• Settlers of Cataan Optional Rules - A variety of optional rules to Settlers of Cataan.
• Settlers of Catan - Official website containing rules, faqs, expansions and variants of the game.
• Siedler von Catan Variants - Rules for Siedler von Catan with two sets and with Entdecker pieces.
• The Settlers of Catan Wikipedia Article - Article covering the history, expansions and video game variants.
• University of Catan - Scenario directory, FAQ and listing of available game products.