In a frantic end to the Q3 shootout, Alonso, Alpine's Esteban Ocon and Ferrari driver Charles Leclerc all traded provisional pole until Red Bull world champion Max Verstappen clinched his first Monaco pole with a hair-raising final sector.
The Dutchman said he "clipped a few barriers" in the process and Alonso also admitted he took a few "uncomfortable risks" in his hunt for his first pole since 2012's German Grand Prix, almost 11 years ago.
With overtaking nearly impossible on the narrow streets, there is annual discussion on whether Monaco deserves to stay on the calendar or whether modern F1 cars have outgrown the principality.
There are also recurring complaints about Monaco's lack of suitable infrastructure and logistical challenges, a result of the paddock being crammed into the tight constraints of its harbour with no clear scope for expansion.
The prospect of a dull Sunday parade remains but, according to Alonso, Saturday's unique qualifying magic shows Monaco - which was part of the the first world championship in 1950 and has been a permanent fixture since 1955 - still has its place in the modern era.
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"I think the lap is high adrenaline and if we see also how it looks on TV, when I was sitting in the car, you see the whole Monaco today on a sunny day, I think is a very unique place," said Alonso.
"Even last year, when there were talks that maybe Monaco was not on the calendar for the future, it doesn't sound right. It has to be, always."
Source: Autosport