The Royal Pavilion, built by the Prince Regent, later to become King George IV, Brighton, East Sussex, England, UK

The Royal Pavilion, built by the Prince Regent, later to become King George IV, Brighton, East Sussex, England, UK

Mosaics and fountain with Lisbon Opera House in the background, Praca Dom Pedro IV (Rossio Square), Lisbon, Portugal, Europe

Praca Dom Pedro IV (Rossio Square) and Lisbon Opera House, Lisbon, Portugal, Europe

Mosaic paving and fountain with Lisbon Opera House in the background, Praca Dom Pedro IV (Rossio Square), Lisbon, Portugal, Europe

Aerial view of Praca Dom Pedro IV (Rossio Square) and city centre, Lisbon, Portugal, Europe

Praca Dom Pedro IV (Rossio Square), Lisbon, Portugal, Europe

Statues and fountain in front of the Lisbon Opera House, Praca Dom Pedro IV (Rossio Square), Lisbon, Portugal, Europe

Statues and fountain with elegant buildings beyond, Praca Dom Pedro IV (Rossio Square), Lisbon, Portugal, Europe

Statues and fountain with elegant buildings beyond, Praca Dom Pedro IV (Rossio Square), Lisbon, Portugal, Europe

The Royal Pavilion, built by the Prince Regent, later to become King George IV, Brighton, East Sussex, England, UK

Aerial view of Praca Dom Pedro IV (Rossio Square) and city centre, Lisbon, Portugal, Europe

Passageway between the Structure IV Annex and Structure VIII, Becan Archaeological Site, Campeche State, Mexico

Structure IV-B, Balamku Archaeological Zone, Mayan Ruins, Campeche State, Mexico, North America

Portal, Structure IV-B, Balamku Archaeological Zone, Mayan Ruins, Campeche State, Mexico, North America

Portal, Structure IV-B, Balamku Archaeological Zone, Mayan Ruins, Campeche State, Mexico, North America

Close-up of bas-relief hieroglyphics painted on the walls of the Royal Tomb of Ramses IV, Valley of the Kings, Thebes, UNESCO World Heritage Site, Egypt, North Africa, Africa