The centre is of medieval origin and dominated by the castle. The town is considered one of the most significant traffic junctions in the region. The Seedam, a dam across the lake of Zurich, links Rapperswil with Pfäffikon on the other side of the lake. This connection has been part of old pilgrimage routes.
The town's main sights are concentrated in the centre and can be seen while strolling through the medieval alleys. The main sights of Rapperswil are its roses, the castle, the wooden bridge to Hurden with its bridge chapel, a chapuchin monastery. There is also a number of churches, chapels, as well as a convent (Wurmsbach) nearby.
Rapperswil is often referred to as the town of roses (Rosenstadt), because of its extensive display of roses in three designated parks. No less than 15,000 plants of 600 different kinds are on display between June and October every year. There is also a park of roses accessible to blinds and disabled in the centre of the town.
The castle of Rapperswil probably dates back to the 13th century. It dominates the old town and is placed on a hill. On the lands surrounding the castle deer are kept. From 1870 to 1927 the castle was home to the National Polish Museum, created by emigrants.
A wooden footbridge led across the lake of Zurich since early centuries. At a lager stage the bridge was replaced a by a dam built out of stone. In 2001 a newly build wooden footbridge was opened alongside the dam for the first 840 metres of the crossing. It was build in the exact place of the original bridge and links Rapperswil with the nearby bridge chapel (Heilighüsli) which was built in 1551.
The chapuchin monastery was established in 1606 and is placed at the lake side. The monastery itself belongs to the citizens of Rapperswil rather than to the monks who inhabit it. This small monastery is still in use.
The main churches in town include the catholic church, the cemetry chapel (Liebfrauenkapelle) and the protestant church. In the surroundings of the town there are a number of churches. The Chapel St. Ursula in the nearby village of Kempraten was built around 885. The St. Dionysius Chapel, dedicated to the first bishop of Paris, was reconstructed in 1493 and attracts pilgrims. The convent of Wurmsbach was established in 1259 and today houses an institute for girls.
There is a zoo (Kinderzoo) located in Rapperswil which particularly aims at children.
Settlements in the region of Rapperswil date back at least 5000 years. The castle was first mentioned in 1229. The town was founded when the nobility of Rapperswil moved from Altendorf across the lake to Rapperswil. The town was soon acquired by the Habsburg family who in 1358 built the wooden bridge across the lake. Later on the town bought itself free and made an alliance with the Swiss confederation.
Because of its stratetic lacation at the centre of trade links the town grew rich. This allowed a certain degree of freedom which was ended with the formation of Swiss cantons by Napoleon. Rapperswil was at first part of the canton Linth but later changed to the canton of St. Gallen.
The locational advantage of the place attracted the national circus Knie who built its headquarters in Rapperswil in 1919. The circus is now also responsible for the zoo and a museum.