A newer alternative to the Blue Lagoon, the Sky Lagoon sits on the rocky south coast of greater Reykjavik (technically just over the line in Kópavogur) and is a fifteen-minute drive from the centre. Its signature feature is a 70-metre infinity edge of warm geothermal water looking straight out over the Atlantic toward Snæfellsjökull on a clear day.
The Sky Lagoon's "seven-step ritual" — warm pool, cold plunge, sauna, mist, scrub, steam, shower — is a polished version of the traditional Icelandic bathing routine. Cheaper and easier to book on short notice than the Blue Lagoon, especially in winter.