Here, bottom-up nanofabrication for the two-dimensional self-organization of highly integrated, well-defined silicon nanowire (SiNW) mesh on a naturally patterned Si(110)-16 x 2 surface by controlling the lateral growths of two non-orthogonal 16 x 2 domains is reported. This self-ordered nanomesh consists of two crossed arrays of parallel-aligned SiNWs with nearly identical widths of 1.8-2.5 nm and pitches of 5.0-5.9 nm, and is formed over a mesoscopic area of 300 x 270 nm(2) so as to show a high integration density in excess of 10(4) mu m(-2). These crossed SiNWs exhibit semiconducting character with an equal band gap of similar to 0.95 eV as well as unique quantum confinement effect. Such an ultrahigh-density SiNW network can serve as versatile nanotemplate for nancifabrication and nanointegration of the highly-integrated metal-silicide or molecular crossbar nanomesh on Si(110) surface for a broad range of device applications. Also, the multi-layer, vertically-stacked SiNW networks can be self-assembled through hierarchical growth, which opens the possibility for creating three-dimensionally interconnected crossbar circuits. The ability to self-organize an ultrahigh-density, functional SiNW network on a Si(110) surface represents a simple step toward the fabrication of highly-integrated crossbar nanocircuits in a very straightforward, fast, cost-effective, and high throughput process.