All right, let's get started, shall we? Section One:  Diamond Interchanges To quote from Mightygoose's Compendium of Interchanges: "A very simple design involving two carriageways, usually perpendicular to each other however other angles are perfectly possible, of different grade (grade being quantity of traffic usually handled). The major grade carriageway in a diamond is referred to as the surface road, as it is customary that the road with higher usage has the least deviation from the horizontal. The minor grade carriageway is reflected to in this case as the street. The street may go either over or under the surface road but it will clearly undergo a greater elevation change if both routes intersect on level ground. Diamonds are the simplest 4 ramp interchanges. They are often used in where there is a very large grade difference in the carriageways such as highways passing through inner boroughs of cities. However they scale up badly. At the ramp/street intersection, unless the street is very low grade, there must be lights. This slows down traffic, and if the street is high grade, cause congestion. Furthermore if the majority of traffic is using only one ramp of the interchange then efficient light timings are going to cause congestion on the street, especially if it is cross-carriageway turning (a left turn in the US or a right in the UK)."quote> Simply put, a diamond is a simple, space-saving low capacity interchange between a highway and a road.  All the road/highway interchanges Maxis included for the elevated and ground highways are diamonds and follow this concept.  Now, I will show you how to make diamonds for the RHW! Getting the basic stuff out of the way This is almost a direct copy of the RHW Readme file, showing how to make a RHW.  I will make a 4-lane RHW with a 1 tile median to keep things as simple as possible. Place your starter pieces... Drag the RHW using the RHW tool... (Optional) Delete the starter pieces to create a RHW without any overrides. And drag the stable network over it. Voila!  You have a RHW!  Now lets make some diamond interchanges for it! Standard RHW-type "A" diamond interchange. From this part forward, the pictures will do most of the talking.  Note, this is just for reference, and your results can be different than mine! Build your overpass.  For this example, I will use a simple road overpass using the NAM raised road pieces.  You can use proper land grading to create a much better looking, realistic result. Get some RHW-2 action going now.  Drag your ramp setup at the ends of the overpass. With those RHW-2s placed as visual examples, you now know where to plop your RHW type "A" ramps: Connect the edge of the ramps up with the RHW-2s, and they should override to create the MIS ramps.  All right!  You have made your first diamond interchange! The same setup can be applied for type "C" Ramps.  Just make sure you leave enough room next to the RHW for accel-decel lanes (RHW-6S). Standard RHW-type "B" diamond interchange. This setup will make the ramps intersect the RHW at a 45 degree angle, which will result in a smaller, better-looking diamond interchange. Do all the steps used in the first guide up to here: Now, instead of plopping the RHW type "A" ramps, plop the RHW type "B" ramps. Now, connect the edge of the ramps up with the RHW-2s and you should get your MIS ramps working. There you go!  Another RHW diamond interchange! Standard "Space-Saving" diamond interchange. Up to now, all the examples I showed were possible with RHW 2.0.  Well, RHW 3.0 is out now, allowing for even more possibilities!  Here is one example. You'll need to construct the overpass a bit differently this time, putting the new RHW/MIS 4-way intersection piece on either side of the RHW. Use the ground to elevated MIS pieces on all four corners of the intersections you first built. And then just use the type "A" RHW ramps to connect everything together. Now, that's quite a space-saver eh? The same setup can be applied for type "C" Ramps.  Just make sure you leave enough room next to the RHW for accel-decel lanes (RHW-6S). Sunken Diamond Interchange Two things you should get before we get started: hole-digging lots and a slope mod. I am going to use both of them for this tutorial.  The end result will look similar to the sunken highway tutorial, but with the RHW! Place your hole-digging lots.  (Hole diggers for sunken.) Drag a road over each to create your hole. Plop road stubs to level the ground properly. Once stable enough, delete the hole digging lots and the road segments. Dig yourself a trench.  Use road stubs for the length of your sunken segment. Once complete, delete the road stubs. Now construct your RHW inside the trench.  Use the steps at the very beginning of this guide for best results.  Create your sunken overpass. Here's where things get tricky.  Extend the sunken segment and create a sloped RHW-2 connecting the road to the sunken segment. -Your results will probably be different than mine! Repeat, 3 more times. Delete any remaining road stubs and level any remaining rugged ground. Plop the new type "A" RHW ramps that separate the RHW and MIS with a 1 tile gap in the remaining sunken areas. You're done!  You can now rest easy. The same setup can be applied with the "space-saver" concept displayed above. Anyways, that will do it for now.  Have fun making some diamond interchanges for the RHW! Best, -Haljackey