Import gpx files

Hi,
I've around 100+ .gpx files which I need to see on google maps all at once.
I need a simple upload feature where I can upload all files at once in a zip and see all my routes on a map.

(www.gpsvisualiser.com allows me to do the same but its limited to importing 8 files at a time. I need to upload unlimited gpx files and want the routes to stay there on the webpage so that any user sees all my routes. Probably this will involve saving routes in some database?)

I'm attaching two gpx files for reference