Huntington Beach has some of the largest stretches of open-sand beaches in all of California, as well the Huntington Beach Pier one of the longest concrete piers in the world, site of world-class surfing and volleyball events yearly.
Running/Walking/biking/rollerblading: There is a wide boardwalk right by the pier. It is part of the Huntington Beach Bike Path. The Bike Path runs for about eight miles along the beach. Heading south along the boardwalk is likely your best scenic scenario. Walking, riding a bike, running are all very safe. Many very good runners first thing in the morning - often as soon as the sun comes up.
Surfing: You can try your hand at surfing. There is a surf rental shop right at the boardwalk. Start with a boogie board for the day circa $15 US. There are many good surfers so they may get annoyed if you stand in the waves too long. Keep moving; this is your best bet. If you get tired get out of their way by heading to the hot sandy beach to rest up for more.
Relaxing: Take a walk up the Main street. There are a number of restaurants and a Starbucks.
Partying: There are so many bars on Main St. that you can meet with friends at any of them and have a great time drinking, dining, or dancing. During the winter, you can organize a "pub crawl" and have your group stop for a drink at every bar.
Peak season is from late May to early September. The beaches on any given summer day may have as many as 500,000 visitors when it is particularly hot inland.
