Sprint Nextel has been promising to phase out its legacy iDEN cell towers for some time, but now it looks like there's finally a roadmap. The company has launched a site that maps out where and when towers are being shut down. If you're in Seattle, the reduction is planned in mid-April; other sites will see reductions throughout the proceeding months, including Las Vegas in early May and Miami in mid-June.

For years now, a decreasing number of prepaid and push-to-talk phones have operated over the iDEN network as Sprint has ramped up its CDMA-based alternatives, and in 2010, the company announced it would be phasing out iDEN altogether to focus on CDMA and 4G networks. At that point, iDEN was slated to go dark completely in 2017, freeing up the spectrum for the CDMA network used by most phones. There's no hint here of when the final transition will occur, but we at least know when the first stage of shutdowns will be taking place.