Standing stones are ancient buildings claimed to have been built by the country's early settlers thousands of years ago. They may be found all around Scotland, but are particularly prevalent in Orkney and Shetland. Yet, to the ordinary Outlander fan, their purpose is as obvious as day: time travel. Historians and archaeologists continue to argue their significance today and believe they were religious places.

We don't fully understand these standing stones, just like we don't fully understand many other aspects of ancient civilizations like the Picts or Nordic settlers. As a result, we are left to make educated guesses, but what is certain is that they serve as magnificent monuments that are well worth a visit.

Let these 13 standing stones and stone circles in Scotland help you travel through time to a time thousands of years ago.

1. Calanais Standing Stones

The standing stones at Calanais, Scotland's most well-known stone circle, are believed to have been constructed around 4,500 years ago during the late Neolithic period. Thirteen stones make up the circle, and a monolith is located not far from the center.

2. Ring of Brodgar

One of the best stone circles in the UK is Brodgar, which was given UNESCO World Heritage Status in 1999. Its exact age is unknown, although experts estimate it to be at least 4,000 years old.

3. Machrie Moor Standing Stones

Six concentric stone circles make up Machrie Moor, which is located on a moor not far from Arran's west coast. Machrie Moor is estimated to have existed circa 2030 BC based on carbon dating of the site's remaining timber.

4. Clava Cairns

While none are known as Craigh Na Dun, you can discover the site that served as the inspiration for the Outlander setting among the numerous standing stones and circles that are dispersed across Inverness. According to Historic Environment Scotland, the Clava Cairns were constructed to lodge the dead and are located in a wooded area east of Inverness, close to Culloden. For millennia, the cemetery was considered a holy site in the landscape.

5. Standing Stones of Stenness

Stenness, which lies less than a mile southeast of the Ring of Brodgar, is considered to be the UK's oldest henge site. Pottery found there connects it to the prehistoric community at Skara Brae. The Stones of Stenness, which were constructed about 5,400 years ago, may be the earliest henge monument in the British Isles, according to Historic Environment Scotland.

6. Balfarg Henge

Balfarg is made up of two standing stones that were once a component of an inner circle inside the henge. It was discovered in the late 1970s during the construction of a new housing complex. At the site, archaeologists found ceramic fragments that date back about 5000 years. Nonetheless, according to certain estimates, some of the construction is closer to 6000 years old.

7. Aberlemno Pictish Stones

Four stones in the settlement of Aberlemno have Pictish sculptures that date from between AD 500 and 800. The Picts were prehistoric Celts who inhabited what is now known as eastern and northeastern Scotland. The better of the three roadside stones in Aberlemno has fine snake, double-disc and z-rod, mirror, and comb symbols, according to the Aberlemno Organization. The third stone is a Pictish cross slab that features an excellent hunting scene on the back and a ring cross on the front.

8. Tomnaverie Stone Circle

The unique type of recumbent stone circle found alone in north-east Scotland is Tomnaverie. It is located in Aberdeenshire, about a mile from Tarland village, on a hilltop. According to experts, a 4,500-year-old burial cairn is encircled by the stone circle.

9. Temple Wood Stone Circle

One of the stone circles in Kilmartin Glen that is thought to be in the best condition is located in this lovely area. The stone circle is thought to have been in use beginning from 3000 BC and continuing up until 1000 BC.

10. Laggangairn Standing Stones

It is said that these two stones are the last two remains of a monument that formerly had 14 stones (in 1873 you could still find seven standing). They have allegedly been present in the New Luce region for up to 4,000 years. Christian crosses with symbolism assumed to date from 600 to 800 AD are etched on the stones.

11. Achavanich Standing Stones

In Caithness, close to Loch Stemster, are the Achavanich stones. Although the bulk of the stones are very modest, it is believed that they weren't always like way. The tallest stone is about 2 meters tall. Their size has degraded due to weathering over time. Furthermore, even though there are only 36 stones left today, there may have once been 54.

12. Tuilyies Standing Stones

The word "Tuilyies," which refers to a fight in Scots, was used to describe the standing stones. Three more sizable stones are located close to Dunfermline, but the most notable stone is an oddly shaped megalith. The "Tuilyies Stane" is the name of the megalith or major stone.

13. Cullerlie Stone Circle

Due to their close vicinity to the village of the same name, Cullerlie is also known as the Standing Stone of Echt. It is made up of eight uneven but beautifully aligned red granite stones surrounded by an equal number of tiny cairns. According to Historic Environment Scotland, the building is 4000 years old.