Along the Kinubari Yama hiking trail is a spot called the Mandaradō Yagura.
If I recall correctly, it is the largest concentration of yagura (burial caves) in Kamakura, with over 150 caves.
Because it’s such an important spot, it’s fenced in, and only opens for a few weeks at a time throughout the year. Unfortunately, we didn’t know that when we set out on our hike, so we had to make due with peeking through the fence.
Even so, it was pretty amazing.