Preheat oven to 325. Layer half of the sheets of phyllo one sheet at a time, in a greased 11x7x2 baking pan, brushing each sheet evenly with butter and folding ends over if necessary to fit into pan.
Keep unused sheets covered with plastic wrap while assembling baklava to prevent drying.
Mix 1/4 cup of the sugar and cinnamon; stir in walnuts.
Sprinkle nut mixture evenly over buttered phyllo in pan.
Layer remaining phyllo, one sheet at a time, over nut mixture, brushing each sheet evenly with butter.
Cut diagonally into squares, cutting completely through all layers.
Bake in preheated oven until crisp and golden, about one hour.
Combine remaining sugar, the water, lemon juice and honey in small saucepan; cook and stir over low heat until sugar dissolves.
Heat to boiling; pour evenly over hot baklava.
Let stand loosely covered 8 hours or overnight.