Volcanic System
Krysuvik
Seltun sits within the Krysuvik-Trlladin volcanic system, one of several active geothermal systems on the Reykjanes peninsula.
Seltun Geothermal Area - Colorful Hot Springs at Krysuvik
A vivid geothermal landscape of bubbling mud pots, hissing steam vents, and sulfur-painted earth on the Reykjanes peninsula.
Updated February 1, 2026By the Iceland.org Travel Team
Location
Reykjanes Peninsula
Krysuvik, Southwest Iceland
Seltun is a striking geothermal area nestled within the Krysuvik volcanic system on Iceland's Reykjanes peninsula. Just 40 minutes from Reykjavik, this accessible site offers a dramatic display of Iceland's underground forces: bubbling gray mud pots, hissing steam vents, and ground stained in brilliant shades of yellow, orange, red, and green by sulfur and mineral deposits. Elevated wooden boardwalks wind through the most active areas, allowing visitors to safely experience the sights, sounds, and unmistakable sulfur smell of an active geothermal field. Seltun provides an excellent alternative to the more crowded Haukadalur area for those seeking an intimate geothermal experience.
Safety + sourcing
Last updated: 2026-02-01
Stay strictly on the boardwalks and marked paths at Seltun. The ground is extremely hot and can be fragile. A steam explosion in 1999 created a new mud pot, demonstrating the area's unpredictable nature.
Sources to check
Distance from Reykjavik
~40 Minutes
Located just off Route 42 on the Reykjanes peninsula, making it one of the closest geothermal areas to the capital.
Admission Cost
Free
Seltun is completely free to visit with no entrance fee. Free parking is available at the trailhead.
What to Expect
Bubbling Mud Pots (100°C+)
Thick gray geothermal mud boils and splatters in natural clay-lined pools at surface temperatures exceeding 100°C. A new mud pot formed during a 1999 steam explosion.
Vivid Mineral Colors
Sulfur (yellow), iron oxide (red/orange), silica (white), and clay minerals (green) paint the ground. Colors are most intense after rain when the wet surface amplifies hues.
Free Admission & Boardwalk
Completely free year-round. Well-maintained wooden boardwalks with information signs take 20-30 minutes to walk. Free parking with restroom facilities.
What to Bring
Sturdy footwear with good grip (boardwalk is slippery when wet or icy), windproof jacket (Reykjanes is windy), and a camera for the extraordinary colors.
Grænavatn Green Crater Lake
A striking green crater lake sits just east of Seltún. Its vivid color comes from algae, sulfur, and dissolved minerals. A dramatic photo stop on Route 42.
Less Crowded Alternative
Only 40 minutes from Reykjavík, Seltún offers a peaceful geothermal experience compared to the crowded Haukadalur area on the Golden Circle, especially off-peak.
Getting There
Seltún is located along Route 42 on the Reykjanes peninsula, approximately 40 km (40 minutes) from central Reykjavík. From Reykjavík, head south on Route 41 toward Hafnarfjörður, then continue onto Route 42 through the Krýsuvík area. A free parking area with restroom facilities is directly adjacent to the boardwalk entrance. No 4WD required -- the route is paved or well-maintained gravel. The nearest town is Hafnarfjörður (30 km). The drive passes the dramatic Kleifarvatn lake and green crater lake Grænavatn. Combine with Gunnuhver hot springs (30 minutes west), the Blue Lagoon (25 minutes), and the Bridge Between Continents for a full Reykjanes day trip.
Best Time to Visit
Year-round. June through August: longest daylight, mildest conditions, and the most vivid mineral colors in bright sunshine. Summer afternoons see the most visitors, but Seltún is always less crowded than Haukadalur. September through October: autumn brings moody skies, fewer people, and colors intensified by frequent rain. November through February: dramatic winter conditions with steam rising against dark skies and snow-covered surroundings. The boardwalks can be icy -- wear footwear with good grip. On clear winter nights, the Reykjanes peninsula is excellent for northern lights viewing. March through May: spring light returns with moderate visitor numbers. Early mornings are quietest in any season.
Planning help
Seltun FAQs
Quick answers with safety notes where it matters.