Helsinki City Library believes that,

The library belongs where all people are, on the streets and in the alleys, wherever people get together, run their errands and live their lives.

For this reason,

the Central Library is taking the skills, information and stories of a library to the people with the help of six bikes, and is inviting them to discover the new and exciting possibilities of doing things together.

The six Christiania tricycles have been used last week for an event promoting the new Library building. The Library will then keep two tricycles on a permanent basis, to maintain the Library’s presence at the heart of the people’s lives. More here.

UPDATE: Here is a similar project in Mannheim, Germany:

finland library