Swimming is a fun way to keep fit, relieve stress, and make friends. A low-impact activity, it provides many physical and mental benefits. Swimming is known to strengthen cardiovascular health, improve muscle strength, and increase flexibility. As one uses nearly all muscles during swimming, the activity provides a complete body workout. It suits folks of all ages and levels of fitness.

For several reasons, one should only swim at legal swimming areas. Water at legal swimming areas is tested regularly to ensure freedom from contaminants such as bacteria. Trained lifeguards at legal swimming areas respond to emergencies and monitor changes in water conditions. Designated legal swimming areas have been surveyed to check for hazardous conditions such as underwater obstacles, drop-offs, or strong currents.

Fortunately, this area has many places to enjoy a nice, safe swim. When planning to swim at a new location, it’s important to note whether the area is open to non-residents as well as residents if you are from out of town.

Some areas charge an entrance fee., and there may also be a fee to park. Many offer season passes, an economical way to go if you plan to swim a lot. Most such areas close if no lifeguard is on duty. Look online or make a phone call before heading out. Always pay attention to signs at the location, particularly those related to parking and safety precautions. Here’s a sampling of local swim spots:

Sandy Pond Beach in Ayer is available at no charge to residents, while non-residents pay a modest fee. In addition to the lake and beach, the park has picnic areas and basketball courts, and visitors may enjoy fishing and birding. Sandy Pond hosted a thriving ice-harvesting business in the years before modern refrigeration.

Spring-fed Mirror Lake at Devens offers swimming, fishing, kayaking, and paddle boarding with swimming lessons and season passes. Be sure to pay for parking and then park in designated areas.

The World War II Memorial Beach in Marlborough, with its beautiful sandy beach, makes a popular spot for swimming. Fort Meadow Lake there has wading pools and provides for swimming with courses in boat safety. A playground, conservation trails, and summer concerts round out the attractions there. Years ago, the American Woolen Company donated the area to the city as a tribute to veterans of the World War II, hence its name..

Harvard residents find a pleasant swimming location at Bare Hill Pond south of town. Although not large, the roped-off swimming area has several rafts. A bicycle trail connects the town beach to school fields. Harvard residents can avail themselves of a boat launching ramp, canoe racks, boat moorings, and picnic tables.

The beach at Nathaniel Allen Recreation Area (NARA) Park in Acton is available to residents and non-residents for a day fee or the purchase of a season pass. In addition to swimming, canoes and paddleboats may be rented. Hungry visitors will find a concession stand as well. A playground and amphitheater with summer concerts round out the fun. The pond was once a quarry with granite mined for building stones, monuments, and curbing.

Groton boasts several legal swimming areas. Sargisson Beach permits swimming, canoeing, kayaking, and fishing, though the beach provides no lifeguards. Knops Pond/Lost Lake, also in Groton, offers similar venues of recreation as well as sailing and powerboating.

The Town of Concord offers a handful of legal swimming areas. White Pond Beach, Rideout Playground, and historic Walden Pond Reservation provide nice areas to swim. The site of Henry David Thoreau’s nineteenth-century woodland cabin has waters some have found too cold even in August, although others enjoy the refreshing change in temperature. Despite frequent crowds in the summer, a peaceful walk around Walden Pond, a glacially-formed kettle pond, can calm the mind.

Swimming provides a relaxing form of exercise and a great way to cool down on hot summer days. Remember to warm up and perform some stretching exercises before entering the water. Watch for sunburn, and stay hydrated. Most of all, have fun!