There are several towers in Amsterdam that you can climb, to enjoy a nice view over the city.
On this page is a list.
Three of them are church towers that are owned by the City of Amsterdam (the towers are separately owned, the church buildings next to them can have other owners), all 3 can be climbed.
View on Zuiderkerk tower
Old Church @ Oudekerksplein
Church in Ransdorp
Westerkerk