The federal government’s vast collection of searchable data has begun to feature information from city databases as part of the effort to increase transparency, promote efficiency and spur innovation.

Now, city officials and developers will work together to help improve the information available to city residents via the new ‘Cities’ Community as part of Data.gov. Databases are currently available for Chicago, New York City, San Francisco and Seattle, according to Jeanne Holm, GSA’s data.gov evangelist. Next up: Santa Cruz, Calif., Louisville and Atlanta.

“The great innovation occurs when people open and share data not just from the government,” Holm said.

The information from cities represents an extension of the original focus of the site, which showcases applications and opportunities for harnessing open data via Communities covering a wide range of related topics.

‘Cities’ includes a huge array of data from city databases such as the location of police stations, construction and housing permits, crime, education and sanitation information. For example, apps aim to help families explore cities, help travelers get to destinations faster and safer, and help residents understand the performance of city government.

The new Community is also launching challenges to encourage participants to produce interesting analyses and applications with city and federal data. Google is asking developers, designers, and tech savvy individuals to improve their community or government using the Google Places API. Grand prize: VIP trip to Google I/O 2013. In addition, Seattle, Washington and King County governments are holding the Evergreen Apps Challenge which is open to people who live, work or study in Washington State. More than $75,000 in prizes are offered for the best apps in a number of categories including a grand $20,000 grand prize.