If I want to go all the way back to the beginning of the gallery, here's what I do:
I use IE, but there should be something comparable in your search engine. From the gallery, in the very upper left of the screen is a box that shows what page your are currently viewing. It looks like this:
See the number 1 at the end (ugh, doesn't show here)? That's the page you are currently viewing. You can increase that number until you reach the end of the gallery or an area that interests you. Then you can view layouts and pages as usual. Currently, there are 54265 pages, but that changes by the minute, LOL.