Migrating the SharePoint 2007 List to SharePoint 2013
One of the elegant solution yet OTB solution available in SharePoint 2013, if you want to migrate the SharePoint list from the SharePoint 2010 or MOSS 2007 to SharePoint 2013.
Large list and item with attachment works charmingly with this solution.
Please check this link , and its really best solution, I would recommend to everyone instead of paying heft huge money for third party software for migrating the OTB stuffs.