Townsville Street Art Trail takes you through 15 works of art hidden in alleys, laneways and on warehouse walls. Head into the city centre for the biggest concentration of murals. The oldest and most well-known piece of guerrilla street art is the ‘Saint’ on Castle Hill — painted in the 1970s in the early hours of Saint Patrick’s Day by local students. It's naive stick figure aesthetic is pure delight.

If visiting an ancient underground passage that has served as a war refuge sounds thrilling to you, then don't miss this fascinating archaeological museum in Naples. More than 500 metres long and 150 years old, the Bourbon Tunnel, Tunnel Borbonico, or Bourbon Gallery has been recently restored to the detail and offers experiences for all tastes, from historical tours to speleological excursions.

The iconic walls of Marrakesh, stretching over 12 km, are more a statement of aesthetic grandeur than a fortification for defence. Originally erected in the early 12th century by the city's Almoravid founders, the walls have undergone several expansions, including the notable addition of the Kasbah to the south and later extensions towards the northern districts. These walls offer an idyllic backdrop for romantic interludes, especially as dusk settles over the city. For those looking to explore further, caleches — traditional horse-drawn carts — are available for leisurely tours around the medina and the ramparts.

Literally named 'Egg Castle', Castel dell'Ovo is a 12th-century fortress that dominates the Naples seafront. The name comes from the legendary Roman poet Virgil, who supposedly strengthened the castle walls with a magical egg.