WASHINGTON (AP) - It's a day of wedding bells for some gay couples in Washington as same-sex pairs began picking up marriage licenses on their first eligible day after the law changed last week.

Fifteen licenses were picked up in the first hour the marriage bureau was opened and two couples already got married and returned to pick up their certificates, courthouse spokeswoman Leah Gurowitz said.

Some couples planned ceremonies the same day at a gay rights group's office while others said they'll wait and have more elaborate celebrations.

About 150 couples were eligible to collect their marriage licenses Tuesday after applying on the first day the licenses were made available last Wednesday. The District has a mandatory three-business-day waiting period.

The District of Columbia is the sixth place in the country permitting same-sex unions. Connecticut, Iowa, Massachusetts, New Hampshire and Vermont also issue same-sex couples licenses. Once couples pick up their license, they have to have the person who performs their marriage sign it and then return it to the marriage bureau to be recorded.

Three morning weddings were planned at the office of the Human Rights Campaign, which does advocacy work on lesbian, gay, bisexual and transgender issues. In the afternoon, a couple had a ceremony planned at All Souls Church _ the same place where DC Mayor Adrian Fenty in December signed the bill legalizing the unions.

Another couple, district residents Eva Townsend and Shana McDavis-Conway, said they were planning a wedding by their plot in a community garden, where they have grown carrots and potatoes.

Other couples said they already had ceremonies and would simply wed at the courthouse, which has space for about 15 people in a ceremony room. Most of those celebrations will take place during the weeks of March 22 and March 29, courthouse spokeswoman Leah Gurowitz.

Normally, the courthouse has four to six weddings a day, but over the next several weeks they are expecting 10 to 12 per day. Some courtrooms and judge's chambers may be used for the ceremonies, with the couple's OK. The court's official marriage booklet has been updated so that the ceremony will end by pronouncing the couple "legally married" as opposed to "husband and wife."

More than 300 people applied for marriage licenses from Wednesday to Friday, almost all same-sex couples, Gurowitz said.