A selection of square mazes. If you add a few straight lines to the many circles, you get additional variation options. So I was able to construct 100 different mazes on the basis of a single grid. Here is a small selection from this series:

Maze 2808
Maze 2823
Maze 2873
Maze 2811
Maze 2821
Maze 2854
Maze 2832
Maze 2896
Maze 2830
Maze 2876
Maze 2888
Maze 2816
Maze 2863
Maze 2835
Maze 2846
Maze 2839
Maze 2880