There are countries in the Balkan area that allow entry if you have a Schengen visa but am not able find a definite list of all those countries. Knowing that will save me getting a visa for all those countries when I do my mega Euro trip.
Since each of these countries would unilaterally decide whether they recognize Schengen visas and under which conditions, I don't think it's possible to find an official list anywhere. I am marking this answer as “community wiki” so that we can come up with a list:
- Bulgaria, Romania, Croatia and Cyprus (all EU members) have rules modelled on those of the Schengen area and allow holders of some types of Schengen visas to visit the country, see Croatian ministry of Foreign and European Affairs, Romanian ministry of Foreign Affairs and previous questions on this site, e.g. Can I enter Romania and stay for four weeks with a Schengen visa?
- Official sources are hard to come by but Albania apparently allow holders of multiple-entry Schengen visa who have already used their visa at least once to visit one of the countries of the Schengen Area, see Wikipedia and Timatic.
- Turkey provides some concessions to those that normally need visas. If you normally need a visa for Turkey, and you hold a Schengen visa - you may be able to avail the new electronic "e-visa" system. The list of countries whose citizens can avail this exemption is mentioned on the Ministry of Foreign Affairs' website.
- According to Wikipedia, multiple-entry Schengen visa holders can visit Bosnia and Herzegovina for 7 days.
- According to Wikipedia, Schengen visa holders can visit Macedonia for 15 days (with some caveats).
Montenegro - According to Visit Montenegro holders of Schengen visas may enter, stay in or cross the territory of Monenegro for up to 30 days (but no longer than the expiry of the visa, if the visa expires in less than 30 days).
There are 19 countries that are not part of the Schengen Area and which you can visit without a national visa if you do hold a schengen visa.
For more information, please have a look at http://www.schengenvisainfo.com/non-eu-countries-where-you-can-go-with-schengen-visa/