There are fairly frequent (about once every half an hour during day time, about 45 minute-intervals during the rest of the day) buses from Istanbul's otogar, with the last bus at 10PM. It takes around two and a half to three hours to get to Vize from Istanbul. They are run by Kale Seyahat.
Kale Seyahat, Istanbul Otogar no: 139, Esenler-Bayrampaşa, ☎ +90 212 658-01-59 (firstname.lastname@example.org), . 18 TL Istanbul-Vize (16 TL if bought online, though you will need Turkish language skills for that). edit
There are also frequent minibuses from nearby cities and towns such as Saray, Çerkezköy (which also hosts the nearest train station), Çorlu, and Tekirdağ to south, and Kırklareli to northwest.
When driving from Istanbul to southeast of town (138 km away, about a one and a half to two hours driving), the most sensible route to take is the motorway (toll-road) O-3/E80 to west until Çerkezköy exit and then proceed via Çerkezköy, and Saray.
From Bulgaria to north, enter the country in Dereköy border gate and after passing through Kırklareli, head east to Pınarhisar which is not very far from Vize.
Hagia Sophia (Greek for "Holy Wisdom") is the common name of a number of Byzantine-era cathedrals and churches across Turkey, with the most notable one located in Istanbul and other remarkable ones in İznik and Trabzon in northwest and northeast of the country respectively.
Hagia Sophia (Gazi Süleyman Paşa Mosque). Primary attraction of the town. While officially named Gazi Süleyman Paşa Camii, this impressive religious edifice made of red brick typical of Byzantine monuments is colloquially called Küçük Ayasofya, i.e. "Little Hagia Sophia", in Turkish. Unlike other Hagia Sophias in Turkey, this former cathedral was never turned into a museum and still is a functioning mosque. Although there is not much art (neither Christian nor Islamic) to see inside the mosque, interior is visitable if the imam is notified, as the gate is locked during non-prayer hours because of a lack of sufficient congregation to keep it open all day.Free. edit
Citadel (Kale), Mimar Sinan Mahallesi. Partially intact remnants of town's citadel can be seen on the pine-covered hill overlooking the town, which was the acropolis deeper in the past. On the foothill below the citadel is also the ruins of ancient amphitheater.edit
Tumulus. Numerous tumulii, or burial mounds built for the rulers of Thracian kingdom, can be seen south of town on the wide open plain. While they can be spotted here and there in much of Eastern Thrace, Vize is one of the places they are clustered together in an exceptionally high number, thanks to the importance the town beared in times gone by.edit
Kıyıköy, or ancient Medea, about 20 km east on the coast of Black Sea, is a historical town with city walls, impressive rock-cut monastery of St Nicholas, and beaches, all surrounded by creeks and forests. Buses departing about once every two hours connect it with Vize.
Demirköy to north, going through beautiful forests of Istranca Mountains, also makes a perfect trip from Vize, although only feasible if you have a car at your disposal. From there on, you can visit a medieval foundary, Dupnisa Cave, and İğneada further to northeast on the coast, surrounded by lush forests and lakes.