There is no password protection, but as a premium customer you can hide the travel diary. After that, the diary is no longer linked either in the overviews nor in the news and can therefore no longer be found on Tripmii. However, if you have a share a link to the blog, users can still access it and have a look at it.
It is important that the diary must still be published so that it can be accessed by others e.g. can be called up to your friends via direct link.