Construction of the access roads, geological survey of the Hiper-Kamiokande cavity, and manufacturing of the first 50 cm diameter photomultiplier tubes.
![Hyper-Kamiokande_2021](https://lsc-canfranc.es/wp-content/uploads/2021/03/Hyper-Kamiokande_2021-1.jpg)
Construction of the access roads, geological survey of the Hiper-Kamiokande cavity, and manufacturing of the first 50 cm diameter photomultiplier tubes.