My fave vacation memories are the visual memories I have (and go back to) of each place in my mind: Amsterdam (LOVE!), Copenhagen, Madrid, Napa Valley, Colorado, San Fran, NYC, Seattle, New Orleans, San Diego, Charleston, Boston, Wash DC, Chicago, Sedona, Portland, Montana, Idaho, The Badlands, Hawaii, Mexico....and more I'm forgetting...all of these places have these little placeholders in my mind that are unique and special.
As far as my dream trip --
our own plane so we can bring our 3 yorkies, and we'd travel all over Europe, Scandinavia, plus Morocco, Egypt, Hong Kong, Tokyo, Bali, Bora Bora, St. Petersburg, Moscow, Nepal...and anywhere else our hearts desired. Our dream trip would include, of course,
hotels that welcomed our 3 dogs and had sound proof walls for them 
.