Marie and Douglas Pyle of Lewisville, Texas, stroll along the 950-foot breakwater that leads to Spring Point Ledge Lighthouse in South Portland during Maine Open Lighthouse Day on Saturday. Visitors say lighthouses are must-see icons of Maine.

Holly Conroy, of Leominister, Mass., rings the bell at Spring Point Light during Maine Open Lighthouse Day on Saturday. Twenty-three lighthouses, including Bug Light and Portland Head Light were opened to visitors.

Visitors gather at the top of Bug Light in South Portland as it was opened to the public for free.

Siblings Avery, left, and Case Lappin, of South Portland, scan the waters for marine life while waiting to enter Bug Light on Saturday during Maine Open Lighthouse Day.

U.S. Coast Guard fireman Justin Busch leads a tour group up the spiral staircase within Portland Head Light.

Visitors take in the view from the top of Portland Head Light.

Visitors could experience a dizzying view from atop Portland Head Light on Saturday. Maine has more lighthouses than any other state.