U.S. National Parks! Yosemite, Yellowstone, Denali, north-rim Grand Canyon
Mesa Verde, all have lodges/restaurants in the park (as do many other park locations inside and outside of the U.S.!)
At Mesa Verde, Chef Brian Puett, hosted 3 sustainable cuisine workshops this fall for visitors to the park (see links).
How about a foodie workshop(s - maybe several locations throughout the country at different times of the year?), wine tasting or a cooking class at the park with time left over to explore and visit with each other?
Our family fell in love with the national parks all over again after watching the Ken Burns' series on PBS in September.
Here are a few park ideas but other National Parks have excellent accomodations as well:
Yosemite National Park, California
Grand Canyon, Ariz.
Yellowstone National Park Lodges, Idaho, Montana and Wyoming
Bryce Canyon, Utah
Olympic National Park, Washington
Glen Canyon Recreation Area, Ariz. and Utah
Denali National Park and Preserve, Alaska
Mesa Verde National Park, Colorado
Shenandoah National Park, Virginia