The deputy chief minister also visited and prayed at Sri Mukhyaprana Hanuman Temple at the entrance of the fort.
Police said the travellers were harassed and attacked when they pulled over in front of a restaurant at Melparamba, 10km from Bekal Fort, Sunday evening.
Activities to preserve the water bodies in the fort will also be undertaken.
People from outside the state and abroad are spending crores of rupees on conducting weddings at Bekal, which holds a prominent spot in Kerala's tourism circuit.
From robotics show and helicopter rides to scuba diving and music concerts, the 10-day event is expected to attract around 5 lakh people.
Kerala is famous for its palaces, forts, stone caves, tombs, shrines, and many other unique architectural features of the state.
The survey will be conducted on 13 stretches of the around 600-km-long waterway and initially, contract has been given for two stretches.
Bekal Fort, a key-shaped structure two-thirds of which juts out into the sea, is a major tourist attraction and a protected monument under the ASI.
The comprehensive storytelling drive will kick-off at Bekal in March.
Beach trekking is quite different from a trekking through forests though some may involve an expanse of wooded area. Five of the best beach trekking sites in India are listed here.