Best way to get from Sevilla to Lisbon

Probably the best way is to take a bus to Faro, Portugal, (2.5 hrs) then switch to the Portugese railway, which is like a giant commuter system. Two bus trips a day at 15 Euro each. Check http://www.eva-bus.com/home.php?lang=UK for bus schedules and tickets (can be purchased 8 days in advance over the internet, or buy on arrival in Sevilla), and http://tinyurl.com/2ywa3w for Portuguese railway times and tickets (about 19 Euro each, 3-4 hours, depending on the train, 5 trains/day, purchase up to a month in advance, or at the station). With four of you travelling together, you won't have a problem. Remember to get all the bus tickets seated next to each other, since buses in Spain have reserved seating. You'll be leaving from the Plaza de Armas bus station in the southwest corner of the "downtown." Rede Bus lines used to have a bus that ran from Sevilla to Lisbon (one daytime trip, 6.5 hours, 39 Euro) but the route may not be running any more. You can check at the Sevilla bus station.