BOSTON -- Some come for the parks and beaches, ocean breezes, walking trails and views of the city and harbor. Others come to appreciate the history of a fort that once protected the city.
For one reason or another, about 1 million people a year visit Castle Island at the eastern edge of the city's South Boston neighborhood.
Walkers, joggers, parents with children and animal lovers with dogs were all enjoying themselves at the park on a recent afternoon. A Coast Guard boat motored by. Jets took off and landed at Logan International Airport across the harbor.
Kathleen Gordon of Somerville was one such visitor. She and her niece, Julia Geary of Quincy, were feeding the birds near the shore.
Gordon says they are frequent visitors because Castle Island is clean, well-maintained, quiet and easy to reach.
"It's open space and it's pretty," Gordon says. "I live in Somerville, where everything's so close together. So this is nice."
Bill Spain, president of the Castle Island Association, a private group that conducts tours of the fort, calls it "the jewel in the Emerald Necklace" of Boston parks.
"It's a good place to go collect your thoughts," he says. "It's got all the great things in life and it's free."
Among the features is the "Sugar Bowl," a circular walkway popular with walkers and inline skaters.
It extends over an enclosed bay to Head Island and to City Point, on the mainland.
There's also the well-preserved fort, which protected Boston through the 19th century. Tours of the fort are run by volunteers through summer and early fall.
For picnickers who didn't bring a lunch, there's a restaurant that sells chicken sandwiches, hot dogs and clam chowder.
Then there's the view. Visible are the harbor islands, planes taking off and landing at the airport, giant container ships loading and unloading at Conley Marine Terminal, and the Boston skyline.
The first fort was established on Castle Island in 1634, and there's been one there ever since. The current Fort Independence, built in 1851 by Col. Sylvanius Thayer, the "father of West Point," was used to train soldiers as well as protect Boston Harbor.
A young Edgar Allen Poe, serving in the army under the last name Perry, served at Fort Independence in 1827. It is said he based his short story, "The Cask of Amontillado," on the true story of a duel between two army officers at the fort in 1817, and a legend about the resulting revenge the loser's friends inflicted on the winner.