Marco Polo at Lisbon, Portugal on December 24, 2011. Photo © Ruí Pais

  Marco Polo at Funchal, Madeira, Portugal on November 6, 2011. Photo © Jorge Humberto Andrade de Freitas

  Marco Polo at Lisbon, Portugal on October 13, 2011. Photo © Ruí Pais

  Marco Polo at Amsterdam, Netherlands on September 17, 2011. Photo © Jan Ramaker

  Marco Polo at Bergen, Norway on August 18, 2011. Photo © Bernd Etzler

  Marco Polo at Tromso, Norway on June 20, 2011. Photo © Robert Wilson

  Marco Polo at Tromso, Norway on June 20, 2011. Photo © Robert Wilson

  Marco Polo at St. Mary's, Isles of Scilly, United Kingdom on April 8, 2011. Photo © Victor Ross

  Marco Polo at Amsterdam, Netherlands on March 22, 2011. Photo © Jan Ramaker

  Marco Polo at Amsterdam, Netherlands on February 22, 2011. Photo © Jan Ramaker

  Marco Polo at Ponta Delgada, Azores, Portugal on February 16, 2011. Photo © António Simas

  Marco Polo at Macapá, Brazil on February 3, 2011. Photo © Gilmar Leal

  Marco Polo at Lisbon, Portugal on January 7, 2011. Photo © João Loureiro

  Marco Polo at Ponta Delgada, Azores, Portugal on December 12, 2010. Photo © António Simas

  Marco Polo at Ponta Delgada, Azores, Portugal on December 12, 2010. Photo © Bruno Rodrigues

  Marco Polo at Funchal, Madeira on October 25, 2009. Photo © Edgar Freitas

  Marco Polo at Tilbury, United Kingdom on September 20, 2010. Photo © Peter Godliman

  Marco Polo at the Isles of Scilly, United Kingdom on August 31, 2010. Photo © Victor Ross

  Marco Polo at Funchal, Madeira, Portugal on April 7, 2010. Photo © Luís Filipe Jardim

  Marco Polo at Funchal, Madeira, Portugal on April 7, 2010. Photo © Guarete Figueira

  Marco Polo at Amsterdam, Netherlands on March 16, 2010. Photo © Jan Ramaker

  Marco Polo at Amsterdam, Netherlands on March 16, 2010. Photo © Jan Ramaker

  Marco Polo at Amsterdam, Netherlands on March 16, 2010. Photo © Jan Ramaker

  Marco Polo at Ponta Delgada, Azores, Portugal on March 10, 2010. Photo © Andre Moura

  Marco Polo at Lisbon, Portugal on January 29, 2010. Photo © Rui Agostinho

  Marco Polo at Funchal, Madeira, Portugal on January 27, 2010. Photo © João Abreu

  Marco Polo at Funchal, Madeira, Portugal on January 27, 2010. Photo © Luís Filipe Jardim

  Marco Polo at Funchal, Madeira, Portugal on January 27, 2010. Photo © Sergio Ferreira

  Marco Polo at Funchal, Madeira, Portugal on November 2, 2009. Photo © Rui Minas Agostinho

  Marco Polo at Funchal, Madeira, Portugal on November 2, 2009. Photo © Sergio Ferreira

  Marco Polo at Ponta Delgada, Azores, Portugal on October 10, 2009. Photo © Bruno Rodrigues

  Marco Polo at Ponta Delgada, Azores, Portugal on October 10, 2009. Photo © Andre Moura

  Marco Polo at St. Petersburg, Russia on September 10, 2009. Photo © Matko Lucic

  Marco Polo at Geiranger, Norway on September 3, 2009. Photo © Dennis Behringer

  Marco Polo at Ponta Delgada, Azores, Portugal on February 28, 2009. Photo © António Simas

  Marco Polo at Funchal, Madeira, Portugal on November 12, 2008. Photo © João Abreu

  Marco Polo at Lisbon, Portugal on November 2, 2008. Photo © Luís Miguel Correira

  Marco Polo at Funchal, Madeira, Portugal on October 31, 2008. Photo © Sergio Ferreira

  Marco Polo at Ponta Delgada, Azores, Portugal on October 8, 2008. Photo © Antonio Simas

  Marco Polo on September 16, 2008. Photo © Vadym Gorbarenko

  Marco Polo at Tobermory, United Kingdom on April 28, 2008. Photo © Thomas Duncan

  Marco Polo at Lisbon, Portugal on April 9, 2008. Photo © Luís Miguel Correira

  Marco Polo at Santorini, Greece on October 16, 2007. Photo © Richard Maidment

  Marco Polo at Sorrento, Italy on September 7, 2007. Photo © Ilja van Wijk

  Marco Polo at Amsterdam, Netherlands on August 27, 2007. Photo © Paul Tang

  Marco Polo at Amsterdam, Netherlands on August 27, 2007. Photo © Paul Tang

  Marco Polo at Velsen-Zuid, Netherlands on June 11, 2006. Photo © Bart de Boer

  Marco Polo at Port Lockroy, Antarctica on February 9, 2006. Photo © Coen Gonsalves

  Marco Polo at Venice, Italy on May 22, 2005. Photo © Nicola Fanchin