Technically the Ring Road could be "done" in 3 days, but a week is a sensible minimum. The following whirlwind itinerary circles the country clockwise, with Reykjavík as the start and finish point. A conventional rental car can easily handle the route, though a 4WD vehicle expands your options considerably, particularly for excursions into the interior. Note: Some museums and other sightseeing stops may be closed outside of summer.
Day 1: Reykjavík
The first day and night is spent in the Iceland's thriving capital.
Day 2: Reykjavík to Sauðárkrókur
Depart early in the morning and head 73km (45 miles) north of Reykjavík, where the Ring Road reaches the town of Borgarnes: The Settlement Center museum offers a surprisingly entertaining and macabre introduction to Iceland's historic and literary roots. Around 125km (78 miles) from Borgarnes, on the north coast, an optional side trip leads around the periphery of Vatnsnes peninsula on Route 711; highlights include the Hindisvík seal colony and the bizarre rock formation Hvítserkur. The unique stone church at Tþingeyrar, just east of Vatnsnes, is another worthwhile detour.
At Varmahlíð, in the Skagafjörður region, turn left on Route 75 toward Sauðárkrókur. Shortly ahead is Glaumbær, the best of Iceland's many museums inside preserved, turf-roofed farm buildings (closing time is 6pm). After dinner in the likeable town of Sauðárkrókur -- if there's still any sunlight -- drive north to Grettislaug for an evening bath in a stone-lined geothermal pool overlooking the fjord.
Day 3: Sauðárkrókur to Akureyri
Today's short drive (120km/74 1/2 miles) allows half a day to get acquainted with Iceland's northern capital, Akureyri. Leaving the Skagafjörður region, the Ring Road ascends through a gorgeous mountain pass surrounded by spiky, serrated ridges. Stop at Halastjarna, a restaurant high in the hills, and build up a lunch appetite with an idyllic, 2-hour round-trip walk to Hraunsvatn
In Akureyri, visit the Akureyri Art Museum, the grandiose Akureyri Church, and Einar Jónsson's poignant 1901 sculpture The Outlaw (Útlaginn). Wind down with the massaging water jets at the Akureyri Swimming Pool, and write postcards at the Bláa Kannan cafe on the pedestrian shopping street Hafnarstræti. If your wallet can stand it, dine at Friðrik V, the best restaurant outside Reykjavík.
Day 4: Akureyri to Mývatn
On your way out of Akureyri, stop at the interdisciplinary Safnasafnið Museum, which opens at 10am. Fifty kilometers (31 miles) from Akureyri, the Ring Road meets the exquisite Goðafoss waterfall. Backtrack 4km (2 1/4 miles), and turn right on Route 85 north to Húsavík, Iceland's whale-watching mecca. (Call ahead if the weather is iffy.) Buy your boat tickets, then bone up before the tour at the Whale Museum. After the 3-hour excursion, choose between the Húsavík Museum (a collection of regional folk artifacts) or the Phallological Museum (a collection of animal penises). For dinner, choose between Húsavík's two best restaurants, Gamli Baukur and Salka. Head back south on Route 85, then take Route 87 to Reykjahlíð village on Lake Mývatn, where you'll spend 2 nights.
Day 5: Mývatn & Krafla
The entire day is devoted to sampling the geological marvels of Mývatn and Krafla. Drive first to Grjótagjá, an eerie fissure and geothermal vent, then take an hour to climb to the rim of Hverfell, a tephra explosion crater. Continue circling Mývatn, stopping at Kalfarströnd Farm for a half-hour loop trail overlooking submerged lava columns. Proceed to the Skútustaðagígar pseudocraters for another 30-minute ramble. Tireless travelers can add the 2-hour round-trip hike up Vindbelgjarfjall to survey the day's triumphs thus far.
Drive east of Mývatn to the Hverir, a hellish geothermal hotspot, then head into Krafla and spend an hour exploring the surreal Leirhnjúkur lava field. On your way back to Mývatn, enjoy a luxuriant, rejuvenating swim at Mývatn Nature Baths. At 6pm, drop into Vogafjós Cowshed Cafe and enjoy a homemade smoked trout appetizer, while cows are milked on the other side of a plate glass window. For dinner, reserve at Hótel Reykjahlíð or the more casual Gamli Bærinn.
Day 6: Mývatn to Seyðisfjörður
The next gas station is far ahead; fill the tank before setting out. About 36km (22 miles) east of Reykjahlíð, exit the Ring Road onto Route 864 and proceed 32km (20 miles) to Dettifoss, Europe's mightiest waterfall. Four kilometers (2 1/2 miles) after the turnoff from the Ring Road, stop at Grímsstaðir Farm and cafe and confirm that road conditions are suitable, and be prepared for a bumpy ride. From Dettifoss, hike 1.5km (1 miles) to the more understated Selfoss falls.
Return to the Ring Road and continue east. In clear weather you should have fantastic views south to Herðubreið, voted Iceland's favorite mountain in a national poll. Sixteen kilometers (10 miles) east of the Route 864 junction, turn right on Route 901 and proceed 8km (5 miles) to Möðrudalur for lunch at the Fjalladýrð cafe. Ask about road conditions further ahead on Route 901, to help choose the best route to Sænautasel, a reconstructed turf farm serving coffee and pancakes in the middle of Nowheresville.
From Sænautasel, return to the Ring Road and continue to Egilsstaðir, the commercial hub of east Iceland. From here it's a 28km (17 miles) detour to the lovely coastal village of Seyðisfjörður, with a breathtaking descent into the fjord. Dinner is at Skaftfell cafe/gallery, followed by a stroll along the harbor.
Day 7: Seyðisfjörður to Höfn
Linger in Seyðisfjörður, walking among the 19th- and early 20th-century chalet-style kit homes. Devotees of outmoded technology should visit the old telegraph station at the Technical Museum of East Iceland. After returning to Egilsstaðir, decide on a route to Höfn, the regional center of southeast Iceland. The Ring Road is the most direct. The longer route -- which affords more Eastfjords coastal scenery -- follows Route 92 to Reyðarfjörður, then Route 96 through a tunnel to Fáskrúðsfjörður and along the coast before it rejoins the Ring Road. Stops along Route 96 include Steinasafn Petru, a local granny's magnificent rock collection, in Stöðvarfjörður. Both routes pass Djúpivogur, a charming fishing village and the launch point for 4-hour boat trips to Papey island. Before dinner at Höfn's inviting Kaffi Hornið, visit the supermarket on Vesturbraut to pack lunch for tomorrow.
Day 8: Höfn to Vík
The 272km (169-mile) stretch of Ring Road from Höfn to Vík is a nonstop procession of stunning scenery. The first requisite stop is Jökulsárlón, an otherworldly lake full of icebergs calved from Vatnajökull, Europe's largest glacier. After another 55km (34 miles), turn into Skaftafell National Park and bring your pack lunch along for a 2- to 3-hour hike to Svartifoss waterfall, the turf-roofed Sel farmhouse, and Sjónarsker viewpoint overlooking an incredible panorama of majestic peaks, looming glaciers, and barren flood plains. In the tiny, isolated village of Kirkjubæjarklaustur, recharge with coffee, bagels, and lox at Systrakaffi. Shortly west of Kirkjubæjarklaustur, exit on Route 206 and proceed 3km (2 miles) to the lovely, contemplative Fjaðrárgljúfur gorge for an hour-long walk along the rim. For dinner in Vík, set out for the casual Halldórskaffi.
Day 9: Vík to Reykjavík
The morning is devoted to Vík's magnificent coastal environs. Allow 3 hours for the round-trip walk along the Reynisfjall sea cliffs to the viewpoint looking west toward Mýrdalsjökull and the Dyrhólaey promontory, identified by its enormous, natural arch of rock. (If this is too much hiking, just stroll on Vík's black sand beach and gaze at the iconic Reynisdrangar sea stacks.) Back behind the wheel, take Route 215 from the Ring Road to the pebbly Reynisfjara beach on the western side of Reynisfjall, and peer into the spellbinding sea cave Hálsanefshellir. If you have time, Dyrhólaey is another enticing side trip, especially for birders. Thirty-three kilometers (21 miles) west of Vík is the Skógar Folk Museum, Iceland's most glorious and affecting collection of folk artifacts. One kilometer (3/4 mile) away is the mesmerizing Skógafoss. Now you can hightail it back to Reykjavík, with a detour to the Fjöruborðið lobster house in Stokkseyri for a valedictory feast.