A few years ago, I realized we are all interlopers in the space of others. This realization was an awakening to the reality that it's up to me to find solitude, rather than expect others to stay home and provide me with solitude. It actually got to the point where I didn't want to do anything on holiday weekends; however, you don't have to go that far.
Holiday weekends are a great chance to spend a few days exploring places that might not otherwise be on your list. I consider them a bonus, and for the most part, I am able to avoid crowds. I'll often spend a Memorial or July 4th weekend seeing fewer people than I see on a typical weekend.
This past weekend, July 4th 2010, the 3 of us spent the entire weekend in the Adirondacks. We didn't fight for a campsite, we didn't get squeezed by crowds, we weren't bothered by noise, and quite frankly while camped, paddling, hiking, or even watching fireworks in Lake Placid, we didn't see more than 20 people all weekend. However, this doesn't fit in with what I saw as I drove through the Adirondacks. Every public pull-out was packed with cars, every pond, lake, stream and trailhead was filled with crowds, it reminded me more of Central Park than Adirondack Park.
So if you hate being an interloper in the space of others, there is still a final 3 day weekend on the horizon, I encourage everyone to break out the maps and guidebooks, and look for something obscure that you probably wouldn't visit any other time. You never know, you might just discover a new "classic" location of your very own!