Recently, I picked up 5 national park quarters, hoping a collector overseas would like to trade. These are great examples taken from an UNC roll and all bear the Denver (D) mintmark. If you would like to trade, send me an email with your ideas.
The set includes these 5 quarters:
* Hot Springs National Park in Arkansas * Yellowstone National Park in Wyoming * Yosemite National Park in California * Grand Canyon National Park in Arizona * Mt. Hood National Forest in Oregon
Here are pics from the US Mint site. My coins are normal UNC strikes.