Before the Arsenal pavilion of the Alexander park , there was a roccoco pavilion built by architect Rastrelli for empress Elisabeth 1st : the Monbijou pavilion :

This pavilion is dismantled in 1819 by scotish architect Adam Menelaws who built a new neo-gothic pavilion : Arsenal , completed by architect Konstantin Thon in 1834 :

Interior view with weapons collection of emperor Nicholas 1st :

Before the restoration :

And now during restoration :
