Travelling to Estonia
In short: Vaccinated are allowed to enter Estonia without restrictions. That includes non EU vaccines (e.g. Sputnik V)
Detailed & updated information about traveling to Estonia can be found here:
https://kriis.ee/en/travelling-crossing-state-border/travelling-estonia/coming-estonia
As of 1 February 2022, travelling gets easier in EU:
https://www.consilium.europa.eu/en/infographics/covid19-travel-measures-eu-january-2022/
Festival
All persons must present a COVID certificate proving vaccination (valid for 270 days or 360 days after booster) or recovery (valid for 180 days) in order to participate the Festival. A COVID certificate is valid with an identification document.
Masks are mandatory inside the venue!
At the moment there is also curfew set to 23:00.