Marklin 59073 - Curved Track R 1394mm
Radius 1,394 mm / 54-7/8". 22.5°. (H1041-2)
Charlie's Tip:
It takes 4 pieces for a 90 degree curve, and 16 pieces for a full circle.
You can select the 59074, it has the same radius, and is 15 degrees (6 pieces for a 90 degree curve).