Major beaches across Korea are opening for the summer season as the country braces for the height of the holiday rush, with coastal cities extending operating periods and adjusting swimming hours to draw visitors. Gyeongpo Beach in Gangneung, Gangwon Province, held its opening ceremony Saturday and will operate for 51 days through Aug. 23. One of the east coast’s best-known summer destinations, the beach has a 1.8-kilometer stretch of sand and is about 70 meters wide. Gangneung’s 17 other beache