Purple martin bird house plans are probably the most complicated bird houses to build. That being said, it's well worth the effort. If you can provide what it takes to attract a colony of these fast flying acrobats they will reward you with many hours of bird watching amazement.
On their annual migration from South America up into mostly eastern United States they stop along their way to breed and raise their young before returning south for the winter. Since they travel in social colonies they also like to nest close together.
Multi room condos, made with your imagination in charge, are very attractive to birds and humans. Twelve to eighteen room units are common, built to look like miniature houses or just a gang of gourds hung together and attractively painted.
Click on this link to learn more about purple martin bird houses and get these free purple martin bird house plans.