Geometrically controlled single-walled carbon nanotube (SWNT) and multi-walled carbon nanotube (MWNT) networks were fabricated by a width confinement technique to characterize their electrical characteristics. The results demonstrated non-linear resistance decay with the number of conducting channels. The current-voltage characteristics at high field were studied until the electrical breakdown took place. Large current (∼2 mA), low resistance (∼5 KΩ) and current densities exceeding ∼108 A/cm2 were demonstrated from multi-channel MWNT networks confined in a 10 μm × 15 μm trench. Additionally, chronological SEM imaging was used to identify the breakdown sequences in the carbon nanotube networks, which revealed a strong tendency for CNT breakdown to occur in the vicinity of CNT-CNT intersections. Our results offer insights for interconnect applications using CNT networks.