re: Most Iconic World Landmarks

Probably known worldwide:
Eiffel Tower
Colosseum
Big Ben / Parliment
Sydney Opera House
Christ The Redeemer
Pyramids/Sphynx
Taj Mahal
Great Wall
Statue of Liberty
Leaning Tower of Pisa
Machu Pichu
Parthenon

Level 2:
Stonehenge
Anghor Wat
Mount Rushmore
Golden Gate Bridge
Mt. Kilimanjaro
Petra
Notre Dame
The Kaaba
Hagia Sophia
Arc di Triumph
St. Basils
The Forbidden City
St. Peter's Square
Dome of the Rock/ Wailing Wall
Empire State Building
LaSagrada Familia
London Eye
Mt. Fuji
The Great Barrier Reef
The Superdome (Katrina)
Santorini (Oia)
Easter Island
Serengeti
The Grand Canal - Venice
Times Square
Buckingham Palace
Grand Canyon
Matterhorn
Dead Sea
Ayers Rock / Uluru
Capri

Level 3:
The Space Needle/ Mt. Ranier
The Gateway Arch
Jackson Square
Chrysler Building
Sears (Willis) Tower
Pantheon
Spanish Steps
Parliament (Budapest)
Plitvice
Angel Falls
Niagara Falls
Victoria Falls
Cappidocia
Duomo - Florence
Burj Khalifa -Dubai
The Pearl - Shanghai
Versailles
Old Faithful
Gibralter
Cinque Terre
Dubrovnik
Louvre

Level 4:
Iguazu Falls
Mesa Verde
Tabletop Mt. (Capetown)
Library at Ephesus
Waikiki and Diamonhead
Genghis Khan statue
India's Golden Temple
White Cliffs of Dover
Blue Mountains/ 3 Sisters - Australia
Grand Tetons
California Redwoods
Meteora Monasteries- Greece
Banf / Lake Louise
Arches National Park
Ring of Kerry
Giants Causeway
South Beach
Brandenburg Gate
St. Chapel