This thread contains a post for each of the Sets designed and built by a dedicated group of TTDPatch artists and coders.
Note that individual graphics that are not part of a Set are not featured here.
There are many web sites such as eis_os's GRFCrawler and Dinges' TTD Graphics site where individual graphics as well as some of the sets are available. The TTDPatch Wiki also has an excellent Graphics download page.
A Set is an assembly of graphics, be they trains, vehicles, buildings, stations, tunnels, bridges, signals, or combinations thereof.
A set follows a theme, usually with a national or continental flavor.
The sets require some version of TTDPatch by Joseph Drexler, usually one of the Alpha versions. They may be found on the TTDPatch wiki here.
The Sets are usually offered for both Windows and DOS versions of TTDPatch.
Many of the sets can be combined providing for a wealth of options all in one game.
This index offers a brief decription of the sets, their authors, and links to their tt-forums threads, their web sites and, if released, their download sites.
******* PLEASE DO NOT POST OR REPLY TO THIS THREAD *******
- tresspassers will be shot - survivors will be prosecuted - / wallyweb
(Edit by Raichase: We are going to trial leaving the thread open for a while, please note that any other posts will be removed and dumped)
Comments should be posted in the "Suggestions" topic or the appropriate Set thread.
(Edit by Raichase: If this thread is ever unlocked, then it is simply for Wallyweb to maintain the thread. Any posts here will be removed. Remember, you have been warned

Acknowledgements: Special thanks and kudos to krtaylor, orudge, Raichase and ThoRune for their help, contributions and encouragement, to Chris Sawyer for a fantastic game, to Patchman and Michael Blunck for taking this game to the next levels and to all the moderators, maintainers, co-ordinators, artists, coders and fans for following in their footsteps and defying math and physics and actually exceeding infinity - the time it takes to enjoy this game.
An Invitation to set co-ordinators and maintatiners ... PM your info per the template in the next post and I'll get the listing up as soon as possible. Thanks.