July 29 (5)

You cant’ take photos (no cameras, not even a phone) in the 4th tunnel (am I getting the numbers right?) – I have vague recollections that you could previously you could… but I might be misremembering. In the 3rd tunnel, there are no restrictions. Walking in the 3rd tunnel is much harder though, I banged my head a few times because of the high unevenness.