Tallinn Gate is the most visible remnant of Pärnu's old fortifications, built when this part of Estonia belonged to the Swedish Empire. It is a compact stone gate rather than a grand fortress, but it gives the old centre a useful historical anchor.
The gate sits between the town and the route toward the park and beach, so it is easy to include on any walk. Pair it with Vallikäär, the nearby moat-like parkland, to get a better sense of how fortified Pärnu once was.