Several local outfits organise a wide range of outdoor activities in and around Bled, including trekking, mountaineering, rock climbing, ski touring, cross-country skiing, mountain biking, rafting, kayaking, canyoning, horse riding, paragliding and ballooning.
There's a cluster of agencies around the bus station, while accommodation providers (especially hostels) can often book you onto their own (or affiliated) tours and activities.
Lake Bled is open to rowboats (motorboats are banned); there are also plenty of summertime stand-up paddleboarders (SUP) on the water. Rental agencies (9am to 7pm May through September) are in various locations, including at the waterfront below the Vila Bled hotel; the Castle Lido; the beach in front of Camping Bled; and the lido by Grand Hotel Toplice. Rowboats generally cost €20 to €25 per hour and SUPs €10.
The 6km-long perimeter path around the lake is suitable for cycling, though the trail is narrow in places and often overflowing with pedestrians. It takes around 45 minutes at a leisurely pace.
There are some excellent mountain-bike trails in the hills surrounding Bled, including the beautiful 13km-long Radovna cycling path that starts in the village Krnica, about 6km from Bled, and runs through Triglav National Park. Pick up a cycling map at the TIC or organise the trip through one of the adventure-sports companies in town.
Fishing is allowed on Lake Bled, provided you have a permit. The surrounding lakes and streams are rich with all manner of river fish.
There are many short and easy, signposted hikes around Bled (numbered signs correspond to numbered routes on local hiking and cycling maps; good maps are available in town for around €6).
One of the best trails is No 6 from the southwest corner of the lake. There, a steep forested path takes about 45 minutes to reach Mala Osojnica (685m), and another 20-minute walk leads to the top of Velika Osojnica (756m). The view from the top – over the lake, island and castle, with the peaks of the Karavanke in the background – is stunning, especially towards sunset. This peak is a photographer's favourite.
Bled's warmish (22°C/72°F at source) and crystal-clear water – it rates a Blue Flag (a voluntary and independent eco-label awarded to beaches around the world for their cleanliness and water quality) – makes it suitable for swimming all summer, and there are decent beaches around the lake, including a popular one near the campground (rich in activity options) and a lovely grass one on the northern side.
The public swimming areas are excellent, and there are a couple of private beaches too, including a refined one at the Grand Hotel Toplice.