Gdańsk Oliwa Archcathedral is a church in Gdańsk, Oliwa, Poland that is dedicated to The Holy Trinity, Blessed Virgin Mary, and St. Bernard.

The archcathedral in Oliwa is a three-nave basilica with a transept and a multisided closed presbytery, finished with an ambulatory. The façade is flanked by two slender towers, 46-metres tall each with sharply-edged helmets. 

It is enlivened by a Baroque portal from 1688, as well as three windows of different sizes and three cartouches. The crossing of the naves is overlooked by a bell tower, a typical element of the Cistercian architecture. 

The cathedral is 17.7m high, 19m wide and 107m long (97.6m of the interior itself), which makes it the longest Cistercian church in the world. It holds works of art in Renaissance, Baroque, Rococo and Classical style of great artistic value.

According to en.wikipedia