The South Rim of the Grand Canyon is about a 250-mile drive from the city. It takes about four-and-a-half hours, which still makes it a reasonable distance to travel on a romantic getaway.
One of the rules of a great escape is that you shouldn't have to spend all of your time in the car. So consider parking yours in Williams and boarding the Grand Canyon Railway.
The train ride takes about two hours, and as soon as you arrive at the depot there's a box lunch and a bus waiting for you. It'll take you on a short tour, which allows time to photograph the Canyon.
If you'd like, stay overnight in the historic El Tovar Hotel, a Grand Canyon landmark that opened in 1905. In honor of its recent centenary it was freshened up, and it's the most luxurious choice for lodging in the park.
The only thing to keep in mind about taking the train, booking a room at El Tovar, or visiting The Grand Canyon on a weekend is that this destination gets very crowded in summer. Reservations are a good idea at any time of year.
But since you live so close, you don't need to travel when the tourists do. Steal away for a romantic weekend in fall or winter, and it just may feel like you have this miracle of nature all to yourselves.