Complex sentence: In 2013, the nickname "Vansterdam" surfaced as a result of the legalization of marijuana in the state of Washington; this is a reference to the cannabis-legal city of Amsterdam in the Netherlands.
Split into simpler sentences: In 2013, the nickname "Vansterdam" surfaced as a result of the legalization of marijuana in the state of Washington. This name is a clear reference to the cannabis-legal city of Amsterdam in the Netherlands.