Sounds through the window

motor boats

squeaky bikes

hoofsteps of horses (police on horseback and horse-drawn-buggy rides)

the church bells

airplanes heading to or from Schipol Airport

motorcycles

police sirens

horns honking for yet another traffic jam

music from car stereos

people talking (every language you can possibly name)

car alarms

drunk men singing

drunk American men playing Marco Polo (I sincerely hope "Marco's" eyes were not closed as he searched for his friends near the canal!) (And how do I know they were American? First of all, they were speaking English, and second - everyone can point out the college-aged American male - the cool dude who struts along the street, bragging loudly about the joint he just smoked so everyone can hear - get a clue, dude! It's legal here so no one cares!)