I go for a walk somewhere pretty, along a canal nearby where the local council puts a lot of effort into making the walking paths nice to look at. It's a lovely escape for me. The stretching of yoga also helps when I don't have time for a walk.
For short amount of time -run a bubble bath and lie in it at night with candles on the edge of the bath, or read a book while soaking up the luxurious bubbles.
This way you don't have to leave the house and drive amongst traffic
In nature! If possible it's nice to go for a short retreat somewhere far away from the city, but if this isn't possible (due to family commitment or limited budget) go to a beautiful local park. All Australian capital cities have lovely botanical gardens which are perfect for relaxation and rejuvenation.