The castle that provided the setting for much of 'Monty Python and the Holy Grail' is now a pilgrimage site for fans.

Built in the 16th century, the tower is now in ruins.

A once extravagant mansion, now reduced to ruin.

The mystery of this small, brick pond eluded its possibly only investigator until his death.

The remains of a 70-year-old military aircraft crash landing still sit on this Scottish hillside.

This waterfall is one of the most spectacular natural features in the Scottish Lowlands.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

A strange rock with a sinister reputation lurks within the crimson waters of this Scottish glen.

A mysterious ruin shrouded in more folklore than fact.

This Scottish bridge seems to compel dogs to leap to their death.

This volcanic plug boasts the longest recorded history of any Scottish stronghold.

One of Scotland's most important modern structures, it just made the '100 Most Endangered Sites' list.

A local tree surgeon has created a whimsical walk full of carved tree stumps near Scotland's Loch Lomond.

A single oak tree rises out of the waters of Loch Lomond.

This ethereal, rainforest-like gorge is home to waterfalls, quaint bridges, and fairy folk.

An 18th-century viewpoint across the surrounding highlands.

A 13th-century stronghold that has fallen into ruin.

The ruins of this magnificent Scottish castle blend both Gothic and Renaissance architectural styles.

Near this coastal cave stands a small memorial to the hermit who made it his home for three decades.

The ruins of a 12th-century seaside castle on the southwest coast of Scotland.

Northern Ireland's church-turned-skate park.

A medieval abbey featured on 'Game of Thrones' that dates back to the 12th-century.

A museum marks and documents the site of the Titanic's launch.

A series of stained glass artworks that depict images of the hit TV show.