How To Go Back To Last Layout?

What is best way to load the last layout the player was just on?

I have a game, which player:

+ Plays Level 1

+ Then Player Goes To Upgrade Area(Layout)

I would like to know how to create events

where The Player can to Go Back to Last Layout

they came from.

Thanks

Store your current level number in a global variable?

Am trying this now... will see how this works.

Thanks.