Lithuanian address cadastre information was opened in October last year. We started importing the data to OSM straight away. Most (90-95%) of addresses could be imported automatically (taking care of existing addresses, putting address on a building when there is only one candidate, removing any excess addresses). Remaining addresses were added semi-automatically using JOSM remote control. This increased the number of addresses from 300 thousand to 1.1 million.

Here is a video of the progress: https://www.youtube.com/watch?v=Eebl0xxT-nM

But we quickly found out that importing addresses is the least difficult part. We have a number of QA rules in Lithuania, including:

• When there is an address with a street S, the way with such name must exist in vicinity
• When there is an address with a city C, it can only be in admin boundaries of city C

Street name information is part of the dataset being opened, but it is way harder to import that data automatically as ways have to be created, combined, split, moved etc. Another thing was that OpenStreetMap data of street geometry is way more precise, so in some cases only human can correctly specify the geometry of the street. Therefore it was decided to go through ALL streets (highway=residential,unclassified,living_street) and add name or noname tag. Several mappers participated using simple report giving JOSM remote control to streets which needed review closest to their starting point. Each mapper started from their own point. This way more than 25000 ways have been reviewed and necessary data added.

Here is a video of name adding progress: https://www.youtube.com/watch?v=Zc3TQQhO_rA

Admin boundary info was also in the opened dataset. It is also being fixed manually. Still in progress.