The Shetland Islands (pop: 23,000), only known to most of us through the eponymous TV crime series, is another archipelago belonging to Scotland. We spent about four days here. The Shetlands represent the northerly extremity of the United Kingdom. They are closer to Bergen in Norway than to major cities in Scotland, and they were ruled by Norway until about 1470AD. Like Orkney, most placenames in the Shetlands have Norse origin, and the islands names are often strange, brief and sometimes monosyllabic, like Unst and Yell. The Shetlands live on fishing, but North Sea oil did wonders for the economy in the late 20th Century, and tourist is obviously significant. There is a movement in Shetland for a greater degree of autonomy from Scottish rule. Humans have populated the Shetlands, well before the Vikings came: it is replete with Neolithic remains, ruins of stone. Nights are very short close to the summer solstice. For our stay, sunset was about 10:30pm, sunrise at 03:30am with a bright twilight in between.
The largest town in the Shetlands is Lerwick on the Mainland, the largest island, founded, apparently by smugglers who found it ideal for their trade. Again, thanks to the NatGeo Explorer's itinerary, we were able to enjoy this town on two seperate days. The NatGeo Explorer dock was within easy walking distance. Lerwick has a decidely British feel arising from its architecture and (lack of) colour, as distinct to Bergen, but the islands cling enthusiastically to their Viking heritage. Prior to one of our arrivals at Lerwick, local immigration officials required a 'face check' for all passengers (quick comparison of our passport photo with our faces). It seems that the immigration procedures on these remote islands depend on where you have come from, and the mood of the officials on the day. More often, any formalities were completed with the purser with a spreadsheet of names over a coffee in the ship's bistro.
Docked in Lerwick, only about 100m from the ship was what might be argued as the most famous house in Shetland, that of the fictional detective inspector Jimmy Perez (played by Douglas Henshall). It's called The Lodberrie and was immediately recognised by fans of the TV series. The word Lodberrie is from Old Norse for landing place, and Jimmy's house is certainly that. Lerwick is an interesting and easy town to walk about. One highlight is Fort Charlotte, with a zig-zag parapet, first built (~1650) to defend against Dutch and French warships, but it has never fired a shot in anger. On top of the town hill is Lerwick Town Hall is a fine building whose clock tower can be seen from far and wide. Plenty of churches, like all Scottish towns, notably St. Columba's and St. Magnus'.
Two brave ladies take to the cold waters of Bains Beach, a favourite haunt of Jimmy Perez, in downtown Lerwick, a replica Viking longboat offshore. 
The adjacent houses in Lerwick have Christmas colours, or are they just Rabbitohs supporters? 
Interpretive signs are helpful, but the grand Lerwick town hall would be better off without these jarring appendages! 
Scalloway and Hamnavoe
Another day, the weather started out 15oC, sunny and still, but grew progressively darker and windier as the morning progressed. On a drive out of Lerwick, we came to Scalloway (Old Norse: bay of the hall) on Mainland, an impossibly beautiful fishing town (aren't they all?) which was the capital of Shetland until the 18th Century. In WW2, Scalloway was a base for the Shetland Bus, a secret fishing boat route into Britain for refugees escaping occupied Norway. Bridges now join Mainland to the islands of Tronda and then West Burra and the town of Hamnavoe, and 'one of the best beaches in Shetland', the Sands of Meal. From here, we could glimpse the island of Foula, which we were to visit another day.
The fishing town of Scalloway showing the ruins of Scalloway Castle, built in 1599 by the brutal Earl Patrick Stewart. Stewart was executed for treason in 1615, and not mourned in Shetland. 
Arnold, a particularly voluble fisherman of Hamnavoe, tells of his life and work as he throws fish to the hungry seals in the harbour. 
Well west of the other Shetland islands is Foula (old Norse for 'bird island'), a privately owned and very picturesque island. It's one of the most remote in the entire British Isles, and after a rough Zodiac ride in, we landed near Foula's only community, neat as a pin, some 35 people, in bright sunshine and no wind. The island has a decent little harbour for such a little place. The island sports some of Britain's highest cliffs (372m) packed with seabirds. Most visitors to this island are birders. We enjoyed a pleasant walk to check out the puffins and fulmars, to visit the island's school (yes, there is one), and to look at an impressive Great War memorial. The four or so children at the school were ready for us, with cakes and scones, and selling handicrafts!
The NatGeo Explorer anchored off picture-perfect Foula, and cliffs populated with nesting fulmars. 
Downtown Foula and the harbour, surprisingly well equipped for such a small island. The shed in the centre of the image has a ferry timetable mounted on the wall. 
When you saw NatGeo Explorer naturalist and photo instructor Steve with this gear, birds will be about! 
Surely one of the world's most telegenic birds, this puffin seems totally unconcerned with human company nearby. 
Arctic skua, known locally as a bonxie, swirling around looking for prey or someone to rob. They are described as kleptoparasitic, animals which steal food from others. 
Off the south-east coast of Mainland is Mousa (rhymes with Noosa, name is from Old Norse for 'moss island'), an uninhabited island which makes Foula look big. The sheep we saw are unattended and are left to roam free for the summer. For our visit, it was fine but cloudy, and we walked a kilometer or so across the 60o north parallel, to the island's main attraction, an intact pre-Viking broch. This 13m tall stone roundhouse is about 2000 years old and is a two walled structure built with local rock with an internal staircase that we were able to climb. Exactly what was inside and on top of this broch when inhabited is uncertain, maybe a lightweight multi-storey structure of timber (but no trees!), and it would have been used as a shelter and lookout tower. The residents would have been farmers. The Orkneyinga Saga (12th Century stories, partly factual, covering Orkney and Shetland) refers to difficult attempts to take the Mousa Broch by force.
Expeditioners from the NatGeo Explorer make their way to the broche on Mousa. Signage warns us not to disturb nesting seabirds. 
Third largest island in Shetland is Unst, the most northerly of all inhabited British Isles. Norse heritage is very strong, and many Viking remains have been unearthed, including 60 Norse longhouses. Having arrived at Baltasound, the port, by Zodiac, we were able to see a replica longhouse based on design aspects from multiple excavations. Next to it was a replica Viking longboat. Unst is blessed with idyllic countryside and must provide total serenity for the 630 residents, but what makes it unusual is that a (controversial) rocket launch site is under construction with the first takeoff scheduled for late in 2023. The Shetland Space Centre plans to launch satellites into polar orbits.
Shallow drafted Viking longboats could be sailed or rowed. Keels were clinker built (overlapping planks), and crews were 25-50. This replica is of a 9th Century boat found in Shetland. 
With ready access, visitors are able to inspect the design and construction aspects of Viking longboats. 
Arctic terms are fiercely protective of their nests, and this one definitely did not like my proximity at Norwick Beach. 
At Unst's Norwick Beach, this fossicker seems oblivious to the frantic swirling of arctic terns overhead. 
A glimpse of the Muckle Flugga lighthouse, the northernmost in the British Isles. The name has Old Norse origins and is thought to mean large, steep-sided island. 
Isle of Noss, Shetland
The NatGeo Explorer did a sail-by along the cliffs of the tiny Isle of Noss (Old Norse: nose), east of Lerwick and once connected to the island of Bressay. Noss has been uninhabited since 1939 and is now a national nature reserve. The sandstone cliffs on Noss, Noup of Noss, have weathered into multiple horizontal ledges making them irresistable as breeding grounds for seabirds, most notably gannets.
In the North Sea
There was unexpected excitement on the NatGeo Explorer when the UK Coast Guard conducted a rescue drill by practicing a winch drop onto the rear sundeck of the ship. Passengers were warned of the drill and instructed to stay indoors, but many of us found a perfect vantage point in the Fitness Centre which overlooks that deck. We were able to see the helicopter apprach from afar and skillfully position itself to lower the 'rescuer' onto the deck. It was an exciting 10 minutes or so!