The LEGO City theme is based on city life with the sets depicting city and emergency services, police, fire, airport, train, construction, and civilian services. The City theme proceeded LEGO Town which was replaced with LEGO World City in before it was rebranded as City in 2005.
2011 LEGO Sets
For collectors, 2011 was a significant year in that LEGO released the first Internal sets Moulding Machines (4000001) and LOM 2011 Moulding (4000002) which have paved the way for high value future collections. A few notable themes introduced in 2011 were Ninjago, Winnie the Pooh, SpongeBob SquarePants, Alien Conquest and LEGO Master Builder Academy. Of course LEGO Ninjago set the stages for a decade of collecting. However, in 2011 LEGO also discontinued a number of themes which included Ben 10, Power Miners, Toy Story, Prince of Persia, Space Police III, BrickMaster and the loved Trains theme.