Visa

For foreign participants: no visa to enter Ukraine is required for citizens of EU, Switzerland, Norway, USA, Canada, Argentina, Japan, Turkey and some other countries.

The list of Countries which have Visa-free Movement Regime with Ukraine can be found at:
http://mfa.gov.ua/en/consular-affairs/entering-ukraine/visa-requirements-for-foreigners

or

http://en.wikipedia.org/wiki/Visa_policy_of_Ukraine