Bulgaria had such a grim reputation during the Communist era that it hardly conjures up images of sun, spas and roses. But these days, travelers are discovering what the vacationing apparatchiks of Eastern Europe knew all along: Bulgaria is a great place to sightsee and relax, from its sunny Black Sea resorts to its charming old towns and cities, pastoral valleys and stunning mountain-enclosed monasteries. In particular, we enjoyed visiting the less-discovered corners of the country, where the modern world gives way to the old. It is odd that in Bulgaria -- a country whose computers once lifted Russian rockets into space -- the horse and cart are still an important mode of transportation.