The ride of twenty-five miles to the capital city is over a series of craters and across the _hraun_ to _Hafnarfjörðr_, Harbor-Fiord, thence by an excellent road to _Reykjavik_. The crossing of the craters is of considerable interest to the geologist. The narrow trail winds down the rim, across the floor strewn with ash and scoriae then up the farther side and thus on from crater to crater till the mountain side is reached then down the mountain side by a winding, troublesome trail to the valley. Here is met as wild a scene of desolation as is to be found in the south of Iceland. The lava flowed over the valley in great billows and out to the ocean. What a commotion that was when the fluid rock slipped hissing into the icy sea, what volumes of steam filled the air, what explosions in the cooling lava as the ocean checked its destructive progress! The lava rises in mammoth blisters with numerous caves that shelter the sheep in the autumn storms. Over all is spread a thin mantle of lichens and within the crevices the Arctic willow and dwarf birch are struggling to reclaim for vegetation this awful wilderness. A wilderness it is, a desolation, a place where witches hung their devil’s cauldrons and brewed their fiendish potions. So intense were their fires that their pots were ruined and when they fled they left the curled and contorted fragments to ensnare the feet of the orthodox traveller. The trail winds down the sides of the cliffs and among the towering blocks in a dizzy fashion. A portion of this territory is called _Sveiflaháls_, Rolling Hills, that is, an undulating mass of lava. On the right rise huge cliffs that have been frost-shattered and at the foot of the narrow ravines that embouche into the plain huge fans of multi-colored rubble are spread above the crumpled rock. From their coverts in the crevices and from within the little caves spring the ptarmigan while the whimbrel’s call is ceaseless from the undulating hillocks. No grass grows here, no sheep scurry before the traveller and not till the _Kaldá_, Cold-River, is reached is there anything for the ponies to eat. This is a delightful place to lunch, this grass grown mound within the river, a tiny island in the midst of ice-cold and sparkling water. The river itself is a natural curiosity, as it rises in several springs from under the mountain, like those at _Hlíðarendi_, flows merrily for two miles and then plunges into a rift to be lost forever, unless it has an underground passage to the sea.