Quarry

x=63
y=63

turtle.digDown()
for i = 1, y do
turtle.forward()
end
turtle.digDown()
turtle.turnRight()

for a = 1, x do
turtle.forward()
end
turtle.digDown()
turtle.turnRight()

for b = 1, y do
turtle.forward()
end
turtle.digDown()
turtle.turnRight()

for c = 1, x do
turtle.forward()
end