Lac de Trémelin

Lac de Trémelin is a lake in the commune of Iffendic, in the Ille-et-Vilaine department of Brittany, roughly half an hour's drive west of Rennes, right at the edge of the Brocéliande forest. The lake sits within a wider domain of more than 220 hectares of woodland, moorland and open water, and the site draws over 400,000 visitors a year, making it one of the busiest outdoor destinations in this part of Brittany.

What is there to do at the lake?

The shoreline is organised around Aventur'O Lac, a leisure base run by the Montfort Communauté. It brings together:

• canoe, kayak and pedal-boat hire,
• a tree-top adventure course with zip lines,
• an equestrian centre,
• beach volleyball, a playground and mini-golf,
• walking and cycling paths that circle the whole lake.

Walking around the domain and enjoying the woodland is free; visitors only pay for the specific activities they choose.

Can you swim in the lake?

Yes. The beach holds the Pavillon Bleu (Blue Flag) label, awarded for water quality and environmental management. Supervised swimming runs through the summer season, generally from late June to the end of August, mostly in the afternoon. Water temperature reaches around 20°C in summer, and a diving platform by the jetty is available for more adventurous swimmers.

Is fishing allowed?

The lake is also popular with anglers. A local fishing association (AAPPMA) manages fish stocks and fishing rights on site.

What else is worth seeing?

L'Aparté, a small contemporary art space, sits within the domain, and a campsite (Camping du Lac de Trémelin) operates right next to the lake for visitors staying longer. During July and August, early-morning guided canoe outings are organised at sunrise - a quieter way to experience the lake before the daytime crowds arrive. A lakeside restaurant and snack bar overlook the water, and picnic spots are scattered around the shore for families bringing their own food.

Who is it suited for?

The mix of a supervised beach, water sports, a tree-top course and family-friendly paths makes Lac de Trémelin an easy day trip from Rennes, and equally a good base for a longer stay in the Brocéliande area, known for its Arthurian legends.

FAQ

How far is Lac de Trémelin from Rennes? About a 30-minute drive west of Rennes, in the commune of Iffendic.

Is entry to the lake free? Walking around the domain is free; specific activities such as equipment hire, the tree-top course or horse riding are paid separately.

When can you swim? Supervised swimming operates during the summer season, generally from late June to the end of August, in the afternoon.

Is the lake suitable for children? Yes - the supervised beach, playground, mini-golf and gentle walking paths make it a family-friendly spot.

Can you stay overnight nearby? Yes, a campsite operates directly on the lakeshore.