In this March 1, 2016, file photo, a sign announcing the closure of Acadia National Park's carriage roads is seen. Credit: Bill Trotter / BDN

Acadia National Park is closing its iconic carriage roads as Maine’s notorious “fifth season” begins.

Park officials said that the 45-mile network of gravel roads will close starting Friday. That comes as warmer and wet weather finally approaches, bringing with it Maine’s mud season, popularly known as the “fifth season.”

The warm and wet weather leaves the carriage roads vulnerable to damage — particularly potholes and ruts — from walkers, bicyclists and horseback riders.

The road network will reopen later this year once the roads dry out and become firm.

But recreaters still looking for a day trip down to Acadia can still use the park’s vast trail network and the loop road, which remains closed to vehicles until April 15.

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