The flag proportion is 1:2 (length twice the width).
The green represents a Gaelic tradition while the orange represents the supporters of William of Orange.
Add to that the opportunity to literally take a walk through Irish history, as this is one of the most iconic urban sites in Ireland, with a strong connection to the history of Northern Ireland.
Having said that, the walk can be slightly depressing on wet and foggy days.
Historically the island has been represented by a number of other flags, including Saint Patrick's cross, and the flag of the four provinces of Ireland.
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Is iad an uaine, an bán, agus an flannbhuí, na dathanna.
Derry City Walls tell the story of Northern Ireland's "Troubles" in a nutshell and are rivaled maybe only by Dublin's General Post Office.
After having been closed to the public for decades, mainly due to them being an ideal vantage point for snipers and the odd stone-throw, the peace process has allowed them to become Derry's most visited attraction.
The white in the centre signifies a lasting truce between the 'Orange' and the 'Green'.
The Irish Constitution says, "The national flag is the tricolour of green, white and orange." The Irish Government defines the offical colours as Pantone 347 green (equivalent to hexadecimal colour code #009A49) and Pantone 151 orange (code #FF7900).