It has a fascinating glass roof that looks like soap bubbles.
Here's the wikipedia article and here's their web site (in Polish).
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On every hour, a trumpet signal - called the hejnaĆ (pronounced hey-now) - is played from the top of the taller of St. Mary's two towers. The plaintive tune breaks off in mid-stream, to commemorate the famous 13th century trumpeter, who was shot in the throat while sounding the alarm before the Mongol attack on the city.You can listen to the trumpet here.
The Continental Army drilled on the lawn and townspeople took refuge here when the British burned the state capital at Kingston, across the river.The Beekman Arms is mentioned in the wikipedia article here and their web site is here.
The Tulip Festival has its origins in World War II when the late Princess Juliana (later to become Queen of the Netherlands) spent the war years in Ottawa. When peace came, she returned home; but she never forgot her stay in Canada. So each year, a gift of over 20,000 tulip bulbs is sent to Ottawa. This year (2005), the festival signals the 60th Anniversary of the end of the war and the Gift of Tulips to Canadians comes as 'A Celebration of Peace and Friendship'.
On the afternoon of Monday, 22nd November, 1869, a beautiful little clipper ship was launched from Scott and Linton's shipyard at Dumbarton. She bore a name that was to become famous...I'll bet you wonder what that little round building is near the Thames. You'll never guess so go read about it here. Then you'll understand this.