You can easily get to Porvoo by bus from many directions. From Helsinki there is frequent bus service daily. From the centre of Helsinki the bus trip to Porvoo takes about 50 minutes by the motorway, and from the direction of Lahti, Tampere, Kouvola or Kotka it's not a long trip either. From Helsinki-Vantaa airport you can reach Porvoo in less than an hour by bus.
Parking places in Porvoo for charter buses.