I've developed some algorithms that work with GPS trajectories. So I need a repository in which I can download GPS trajecotries to run my test.
I most need marine and air tajectories, better if fileformat was a .gpx.
GPS track logs for vessels can be accessed using AIS.
Ships broadcast information such as GPS position, heading, and speed. Updates are sent over radio at periods of between 2 and 30 secs for a moving ship.
Data can be accessed on sites such as aprs.fi who provide an api, although not in GPX format. Many commercial sources also exist that can provide historic data.