Fair Isle, rock-bound, precipitous and lonely, with but one or two small creeks where vessels may shelter, has two lighthouses, each with a fog-siren and a group-flashing white light—the Scaddon, visible 16 miles, and the Scroo, visible 23 miles. It was on Fair Isle that _El Gran Grifon_, one of the Armada ships, was wrecked in 1588. [Illustration: Sumburgh Head and Lighthouse] Sumburgh Head, the most southerly point of the Mainland, is also capped with a lighthouse, perched 300 feet above the swirling eddies of the Roost. Erected in 1820, it was the first lighthouse on the Shetland coast. Its group-flashing white light is visible 24 miles in clear weather. North of Sumburgh Head are Grutness Voe and the Pool of Virkie, with their low-lying sandy shores; while near by are Sumburgh House and the ruins of Jarlshoff. From this point northward the coast is rocky, with moderately low cliffs, which are broken up by the inlets of Voe and Troswick. The next conspicuous point is the headland of Noness, crowned by a small, quick-flashing white light, a guide to the busy fishing centre of Sandwick, and the fine sandy bay of Levenwick, which lies directly opposite. Passing through Mousa Sound, we have on the right the low-lying grazing island of Mousa with its famous Pictish castle, and on the left Sandlodge, near which are disused copper-mines. Two miles north of Mousa is the low-lying point of Helliness, having at its base the small harbour of Aithsvoe. From here onwards the coast is of varying heights, and broken by the exposed creeks of Fladdabister, Quarff, Gulberwick, Sound and Brei Wick. Bressay lighthouse, which has a revolving red and white light, visible 16 miles, shows the way to Bressay Sound and the harbour of Lerwick. [Illustration: Bressay Lighthouse and Foghorn] [Illustration: Cliff Scenery, Noss. Bressay] The shores of Bressay are low-lying on the west and north; but on the south are the high cliffs of the Ord and Bard, the latter having the Orkneyman’s Cave and the mural arch of the Giant’s Leg at its base. On the east side of Noss Isle the cliffs are also high, forming the favourite breeding-ground of myriads of sea-birds. The diversity of the coastline, with the sudden transition from an uninteresting shore to bold, precipitous cliffs, is owing to the dip of the rock-strata. If the dip is to the sea, there is a more or less gradual slope _to_ the shore; but if the dip is _from_ the sea, then there is the towering cliff, facing the waves like a giant wall. A good example of this is in the island of Noss, which is 592 feet high at the Noup, and gradually slopes down to near sea-level at the western side. The general outline of the cliffs, too, depends on the texture of the rocks. With sandstone, they tower up in regular layers like a wall, bold and massive, with clear-cut caves and tall stacks. With schistose and granite rocks, however, the cliffs are more broken and rugged.