Congress President Rahul Gandhi on Sunday flagged off a marathon to promote environment and ran with a few participants at the historic Gol Gumbaz monument in north Karnataka's Vijayapura district.Clad in yellow T-shirt and blue jeans, Gandhi joined party's state unit leaders and cadres who assembled at the 17th century tomb of king Mohammed Adil Shah for the "Vrukshathon 2018" with a call to conserve water and protect trees.Party's state unit president G. Parameshwara, party's state in-charge and Lok Sabha member K.C. Venugopal and state Water Resources Minister M.B. Patil also ran with Gandhi for a distance along with hundreds of local youth.Gandhi is on a three-day visit to the state's northern region since Saturday on the 'Jan Ashirwada Yatra' ahead of the state assembly election in late April or early May.Gandhi offered floral tributes and prayers at the Chikkapadasalagi reservoir built across river Krishna in the neighbouring Bagalkot district, expressing gratitude to nature for copious rains filling the dam.He garlanded statue of Mahatma Gandhi at Jamkhandi and held road-side meetings with people, including farmers and women from self-help groups."Gandhi also interacted with party workers and supporters at Bilagi and Lakhapur and addressed a public meeting at Mudhol in Bagalkot district," a party official told IANS.Gandhi is on the second leg of the visit to the state this month after a four-day trip to the seven districts of the region earlier this month.