Complex sentence: Victoria and Albert were on a visit to Duke of Atholl and his nephew, Lord Glenlyon (who succeed the unmarried duke 2 years later); the royal boat landed at the Royal Arch; the couple returned and embarked for London on 1 October 1844.
Split into simpler sentences: Victoria and Albert were on a visit to Duke of Atholl and his nephew, Lord Glenlyon (who succeed the unmarried duke 2 years later). The Royal boat landed at the Royal Arch and the couple returned and embarked for London on 1 October 1844.