Man-made curves:
Photo 1:
Piggy

This is my sons piggy. When I thought about a man-made curves this is the first thing that I thought about. It is so curvy! The body, the nose, the legs...well everything except from the ears. I wanted to take the photo with a line background so I took it next to the couch.
Photo 2:
Round building
A building in Stowe Gardens. Here too the building is curvy as well as his balcony, pillars and ceiling, all perfectly shaped.
Nature made curves:
Photo 3:
A path
For me, the entrance to this path is a beautiful ellipse curve which gives it a feeling of a magic entrance.
Photo 4:
Swans
In this photo there are 2 main nature made curves: the swans neck and the circles the swans makes in the water. I feel like this curves gives the photo a 'Royal' look.