Build your modern high-speed rail network with the latest additions to our snap-fit E-Z Track system! Our new Concrete Tie Track with Nickel Silver Rails will look the part on any modern era mainline railroad from the BNSF Transcon to the Amtrak Northeast Corridor. 18 Radius Curved Track is the basic curve of the E-Z Track system. It can also be placed on the inside of 22 radius curved E-Z Track for double-track mainline realism. Four pieces of track make up one-third (120 degrees) of a 36 diameter circle.