The Florence Griswold Museum, 96 Lyme Street, will open “‘A Pretty Fine Old Town’: Childe Hassam in Old Lyme” on June 5. This new exhibition features more than 20 Hassam paintings from museums and private collections and is designed to give a picture of the artist’s pivotal contribution to the Lyme Art Colony as a leading center of Impressionism. The show will run through September 26.

After Childe Hassam (1858-1935) first visited Old Lyme in the summer of 1903, he wrote to his artist friend J. Alden Weir in Branchville, Conn., “We are up here in another old corner of Connecticut, and it is very much like your country. There are some very large oaks and chestnuts and many fine hedges. Lyme, or Old Lyme as it is usually called, is at the mouth of the Connecticut River and it really is a pretty fine old town.” He stayed at Florence Griswold’s boarding house, home of the Lyme Art Colony, and now the Florence Griswold Museum.

Hassam’s charm and easy manner made him a favorite of “Miss Florence,” as Griswold was affectionately known. During his frequent trips to Old Lyme over the next several years Hassam was given the best studio on the property, next to the garden overlooking the Lieutenant River. A painting of his studio by Harry Hoffman is in the exhibition.

Hassam was staying at the Florence Griswold House in 1905 when he began to work on the monumental painting “June,” a highlight of the exhibition. This mural-size painting portrays three nudes among the mountain laurel bushes on the banks of the Lieutenant River. It is on loan from the American Academy of Arts and Letters in New York and has not been on public view in more than 90 years, when an entire gallery was devoted to it at the Carnegie Museum of Art in Pittsburgh.

Educational programming will be highlighted by performances in July of an original one-act play, Hassam in the Garden.

For tickets call 860-434-5542, ext 111. For information, www.flogris.org.