We present an 8 × 8 superconducting nanowire single-photon detector (SNSPD) array that addresses the trade-off between detection efficiency and count rates in large-area devices. The SNSPD array employs a distributed nanowire architecture and a polarization-insensitive optical cavity, when coupled with a 105-μm multimode fiber, achieves a system detection efficiency of over 65% at 1064 nm, a maximum count rate (MCR) of 1.2 GHz, and an average timing jitter of <100 ps. This design offers a scalable solution for high-speed photon counting with large-area detection and multimode compatibility.