Three-dimensional (3D) writing is a promising approach to realize stretchable electronics, but is so far limited to microscale features. We developed accurate 3D writing for highly stretchable organic nanowire arrays using a nanoscale polymer meniscus. Specifically, 3D nanoarches of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) with unprecedented stretchability, over 270%, and no compromise on the electrical characteristics were fabricated. Then, we integrated nanoarches into photoswitches, electrochemical transistors, and electrical interconnects. The impact of these successful tests goes well beyond these specific devices and opens the way to new classes of stretchable nanodevices based on organic materials.