In years gone by there were all kinds of wierd theories as to how the birds and bees navigated. Navigation by the sun, by the earth's magnetic field, theories dreamed up on the basis bees (and even birds) couldn't possibly have the intelligence to learn their way home. It's only recently scientists have acknowledged the birds and bees actually learn their routes using landmarks such as large buildings, rocks, hedges, trees, roads etc. Very much the same way we learn to navigate.