The Thames River Quest, "a free, treasure-hunt style educational hike at historic sites on the New London and Groton sides of the river," will take place for a second year on Connecticut Trails Day on June 1, according to a news release.

A “Hidden Thames Street” hike in Groton has been added to the original three hikes, at Fort Trumbull State Park and the downtown waterfront park in New London and at Fort Griswold Battlefield State Park in Groton.

Also new this year is a shorter and easier Quest hike for Fort Trumbull to give more participants time to take advantage of the free water taxi and complete the other hikes, the release states.

The water taxi, which is free of charge from 10 a.m. to noon on June 1, will take participants between Fort Trumbull, the waterfront park and the municipal dock on Thames Street in Groton that provides access to Fort Griswold and to the portion of Thames Street where the “Hidden Thames Street” Quest takes place.

For each of the four Quests, participants will follow a series of clues from downloadable PDFs that can be printed at home and will be available on May 31 at bit.ly/TRHPquests. Hikers will learn about the history and ecology of the river while solving a word puzzle that leads to a treasure box.

Participants can start at Fort Trumbull at 90 Walbach St., New London; the New London Waterfront Park at City Pier, 1 Waterfront Park, New London; or Fort Griswold and Thames Street at 301 Thames St., Groton.

The Quest hikes were created by a partnership of Connecticut Sea Grant and the Thames River Heritage Park. In addition to Connecticut Sea Grant and the Thames River Heritage Park, the Thames River Quest also is being sponsored by The Day Publishing Co.

For more information and to register for one or all four of the Thames River Quest hikes, visit bit.ly/TRHPquests. Registration information also is available on the Connecticut Trails Day website, bit.ly/CTtrails19.