SAN FRANCISCO -- The city's annual gay pride parade and celebration this weekend is already one of the largest in the country, drawing as many as one million people to downtown on past June weekends.

Adding to the cheering, music and the full-throttle "vroom" from the San Francisco Dykes on Bikes® Women's Motorcycle Contingent, will be the ringing of wedding bells and cheers of joy from marriage proposals.

With the U.S. Supreme Court on Wednesday paving the way for same-sex couples to marry in California, and striking down the 1996 law known as the Defense of Marriage Act, or DOMA, the party is expected to be bigger than ever.

At the 43rd annual free celebration, there will be more than 200 parade contingents, 300 exhibitors, and more than 20 stages and venues with musical acts and entertainment.

If you are going to the "Embrace, Encourage, Empower" celebration and parade, here are a few things to know:

  • Bring water, sunscreen, snacks and a hat. It's going to be warm, especially with hundreds of thousands of people jammed together in the streets. The National Weather Service is predicting mostly sunny skies, with a high near 76 degrees, and light winds.

  • Take BART. Although BART has authorized a strike when union workers' contracts expire at 11:59 p.m. Sunday, the transit agency will on Saturday and Sunday provide longer trains to accommodate the crowds. BART officials are urging people to purchase a round-trip ticket as they enter the system to avoid lines at ticket machines, or use a pre-loaded Clipper card. For more information, including real-time train arrivals and departures, go to www.bart.gov.

    San Francisco Police Chief Greg Suhr said new estimates for Sunday's Pride Parade are at 1.5 million people. Police are warning people to be cautious, keep wallets, purses, cell phones, iPods and other valuables out of sight and report suspicious people or activity to the many officers who will be on the streets.

    If you had planned to drive to San Franciscothis weekend, transportation officials are urging you to avoid Market Street, the downtown and Civic Center areas and the Castro district as the crowds and street closures will making driving difficult. For real-time updates on road conditions, check www.511.org.

    Muni transit officials are advising riders to plan ahead and expect rerouted buses and limited service throughout many parts of the system.

    Information is available at www.sfmta.com/calendar/san-francisco-pride.

    Here's a look at some of the fun and free events happening this weekend:

    Saturday

  • At 7 a.m. the 18th annual display of the Pink Triangle, which uses 175 pink tarps and nearly 5,000 steel stakes to create the giant piece of social justice art, will go up on the hill on Twin Peaks.

  • At 10:30 a.m. a ceremony will begin with San Francisco Symphony Director Michael Tilson Thomas. Also expected to attend are: state Sen. Mark Leno, state assemblymen Tom Ammiano and Phil Ting, San Francisco supervisors David Chiu, Scott Wiener, David Campos and Malia Cohen.

  • From noon to 6 p.m. the San Francisco Civic Center will be abuzz with musical acts, including 20 stages featuring DJ Lezlee, Ms. Jackson, Kidd Sysko, performances and countless dancing opportunities along with community groups and food, beverages and Pride merchandise for sale.

  • At 5:30 p.m. the annual free Pink Saturday party is held on several blocks of Castro Street starting at Market Street by the Sisters of Perpetual Indulgence. The alcohol-free event will include music and entertainment.

  • From noon to 5 p.m. the "Dykes on Bikes" will be at El Rio, 3158 Mission St. for a party and barbecue. The San Francisco Dyke March will have music and performers at Dolores Park from noon to 5 p.m. and then march to the Castro district at 6 p.m.

    Sunday

  • At 10:30 a.m. the parade, with at least 200 contingents, winds down from Market and Beale streets to the Civic Center. Celebrities and activist grand marshals include "Glee" star Alex Newell, "Project Runway" designer Mondo Guerra and Tabatha Coffey of Bravo's "Tabatha Takes Over."

  • From 11 a.m. to 6:30 p.m. the Civic Center will play host to up-and-coming talent, world-renowned performers and Bay Area entertainers, including Raquel Rodriguez, Gypsy Love, Lovesick Radio, Xavier Toscano Hedwig & the Angry Inch, Nina Sky and many more. State Attorney General Kamala Harris, with Lt. Gov. Gavin Newsom and San Francisco Mayor Ed Lee, will also take the stage on Sunday. There will be 300 exhibitors at the event.

    A suggested minimum donation of $5 at the celebrations will help keep San Francisco Pride free to all in coming years. For more information, go to www.sfpride.org.

    Contact Kristin J. Bender at kbender@bayareanewsgroup.com. Follow her at Twitter.com/kjbender.