The On-Chip High-Field Nanophotonics Incubator will explore scientific and technological opportunities at the confluence of nanophotonics and high-field femtosecond to attosecond physics. It will address how, and if, nanostructured solids can be utilized to explore the rich physical landscape of high-field nonlinearities, characterized by the emission of high harmonics and controlled generation of free carriers and petahertz currents.