Bled is a natural base for the Julian Alps. The most obvious half-day trip is Lake Bohinj, 26 km southwest — bigger, wilder, and far less developed than Bled, with the gateway to Triglav National Park and a cable car up Vogel for high mountain panoramas.
Kranjska Gora, 40 km northwest, is the major ski resort in the Slovenian Alps and the start point for the spectacular Vršič Pass road over to the Soča Valley. The medieval town of Škofja Loka, 30 km south, makes a lovely afternoon for anyone interested in well-preserved old towns. And Ljubljana itself is only an hour away by direct bus or train if you want a complete change of pace.
For walkers with a full day, the trail from Mala Osojnica round the western end of the lake and down to the village of Bohinjska Bela is a quiet alternative to the crowded lake-shore circuit.