Producing nanostructures with embedded bright ensembles of lifetime-limited emitters is a challenge with potential high impact in a broad range of physical sciences. In this work, we demonstrate controlled charge transfer to and from dark states exhibiting very long lifetimes in high-density ensembles of SiV centers hosted in a diamond nanopyramid grown by chemical vapor deposition. Further, using a combination of resonant photoluminescence excitation and a frequency-selective persistent hole-burning technique that exploits this charge state transfer, we could demonstrate close to lifetime-limited linewidths from the SiV centers. Such a nanostructure with thousands of bright narrow linewidth emitters in a volume much below λ3 will be useful for coherent light–matter coupling, biological sensing, and nanoscale thermometry.