The Church of St. Adalbert is one of the oldest stone churches in Poland. The Church was built in the 11th century and named after the martyred missionary Saint Adalbert whose body was bought back for its weight in gold from the pagan Prussia and placed in Gniezno Cathedral by Boleslaus I of Poland. The interior of the church is cramped, relative to its larger exterior. The floor level is situated under the present level of the Square, which reflects the overlaying of the subsequent surfaces of the plaza with pavement originally adjusted to the two already existing churches (St. Wojciech/Adalbert and St. Mary's Basilica). The church was partially reconstructed in the Baroque style between 1611-1618.
According to the Archeological Museum of Kraków, the oldest relics reveal a wooden structure built at the end of the 10th century and followed by an original stone church constructed in the 11th century, as seen in the lower parts of the walls. These walls became a foundation for a new church built around the turn of the 11th and 12th centuries from smaller rectangular stones. Since the level of the plaza, overlaid with new pavement, rose between 2 to 2.6 meters, the walls of the church were raised up in the 17th century and then covered with stucco. The new entrance was built from the west side and the church was topped with the new Baroque dome. The restoration of the church conducted in the 19th century led to the discovery of its Romanesque past.
At present, the walls of the church are unearthed to show their lowest level. On the south side there's a Romanesque portal and corresponding stone step. The crypt of the church has been adapted by the Archeological Museum as a small Museum of the History of the Market Square showing a permanent exhibit of 'The History of the Kraków Market.'References:
Built around AD 90 to entertain the legionaries stationed at the fort of Caerleon (Isca), the impressive amphitheatre was the Roman equivalent of today’s multiplex cinema. Wooden benches provided seating for up to 6,000 spectators, who would gather to watch bloodthirsty displays featuring gladiatorial combat and exotic wild animals.
Long after the Romans left, the amphitheatre took on a new life in Arthurian legend. Geoffrey of Monmouth, the somewhat imaginative 12th-century scholar, wrote in his History of the Kings of Britain that Arthur was crowned in Caerleon and that the ruined amphitheatre was actually the remains of King Arthur’s Round Table.
Today it is the most complete Roman amphitheatre in Britain.