In what countries is incest legal if any where can siblings marry?

It’s a pity, but I think you can’t find any country, where you can marry your own sister. But consensual incest is not prohibited in France, for example. You can go there and have all the sex in the world with your sister (just don’t make her pregnant!) but still you can’t marry her. Sweden is the only country in Europe which allows marriage between siblings who share one parent. And stay away from Germany - they can put you in jail for banging your sister.