The life of Rabbi Shimon Bar Yochai is celebrated on Lag B’Omer. His mentor Rabbi Akiva supported Bar Kochba in his 134-136 CE revolt against Roman occupation of Judea. So, it was apt that this year on Lag B’Omer, archaeologists found a coin minted by Bar Kochba’s supporters.

http://www.jewishpress.com/news/israel/discovery-of-bar-kochba-era-coin-declared-at-lag-bomer/2018/05/04/