What are the best day trips from Charleston?

Beaufort over Savannah for couples who want a full day without highway fatigue. The drive south on US-21 is 70 miles, about 1 hour 20 minutes each way. Bay Street runs along the Beaufort River, and on weekday mornings you'll have the waterfront benches mostly to yourselves. Live oaks along the Waterfront Park trail drip Spanish moss low enough to brush your shoulder. Lunch at Plums on Bay Street runs $12-28 per plate, and the shrimp and grits there use stone-ground grits that taste different from Charleston's restaurant-supply version. The Pat Conroy Literary Center is free and takes 30 minutes. If one of you wants to browse the shops on Port Republic Street while the other reads on a waterfront bench, you're 3 blocks apart. Back in time for dinner in Charleston by 6:30pm.

Savannah is the obvious big-ticket day trip at 108 miles south on I-95, but be honest with yourselves about the timeline. Leave Charleston by 8am to get a full day. All 22 squares are worth the walk, and Forsyth Park's fountain is one of the few sights that looks like its photograph. Mrs. Wilkes' Dining Room on West Jones Street opens at 11am, and the line forms by 10:15. Communal tables for 10, so not a romantic lunch, but the fried chicken and sweet-potato soufflé make the trade-off easy. For a quieter meal, The Grey on Martin Luther King Jr. Boulevard occupies a converted 1938 Greyhound station where the bar seats face the open kitchen. The realistic math is 5-6 good hours in town before the 2-hour return. That's enough for 8-10 squares, one sit-down meal, and a cocktail at Artillery on Bull Street. Not enough for both the Telfair Museums and a leisurely lunch. If history is one partner's priority and wandering is the other's, split for 2 hours and meet at the fountain at 3pm.

For a beach day where neither of you has to perform enthusiasm for museums, Edisto Island is 50 miles southwest and feels like the South Carolina coast before the condo boom. No hotels over 3 stories. The beach smells like pluff mud and salt, and the sand is packed hard enough to walk barefoot for 2 miles without hitting a resort fence. The island has a handful of restaurants on Jungle Road, with fried seafood baskets running $14-18. Kiawah Island, 25 miles south, is the upscale alternative with a 10-mile beach, but non-guest beach access costs $10 per car at Beachwalker Park, and parking fills by 10am from June through August. Between the two, Edisto is better for couples who want to read under an umbrella with cold beer and no schedule. Kiawah works if one of you wants a proper resort lunch while the other bikes the nature trails.

Congaree National Park sits 115 miles northwest, about 2 hours on I-26. The Boardwalk Loop Trail is 2.4 miles, flat, and runs through the tallest canopy of old-growth bottomland hardwoods on the Atlantic coast. In late August the air under that canopy is warm and heavy at 89% humidity, and the mosquitoes are aggressive. Bring DEET. Worth it for the couple where one person wants a 3-hour walk and the other is content on the flat boardwalk with a book. Georgetown, 60 miles north on US-17, is the lower-key alternative to Beaufort. The Harborwalk follows the Sampit River, and the Rice Museum on Front Street ($7 adults) explains the plantation economics that shaped this coast. The town tends to empty by 3pm, which means you might have the River Room's waterfront tables to yourselves for a $22-35 dinner before the drive back.