Organisers of the Glasgow Pride event have apologised after hundreds of people who had bought tickets were denied entry and told it had reached capacity.
Long queues formed at Kelvingrove Park with tickets seemingly oversold and many people took to social media to complain.
Organisers posted on Facebook: "The interest in Pride Glagsow today has far exceeded our expectations, our parade had over 12,000 march, the largest number in our history.
"Glasgow Pride apologises unreservedly to those people who purchased tickets and were unable to enter the site."
Glasgow Pride added: "Police Scotland are present at Kelvingrove Park to support the Pride Glasgow event organisers and stewards to ensure the safety of those attending the event."
The music event followed a march led for the first time by Nicola Sturgeon.
The First Minister said leading thousands of marchers at Scotland's largest lesbian, gay, bisexual, transgender and intersex (LGBTI) pride event was a "real honour".
Wearing a T-shirt with a rainbow coloured "choose love" logo, the First Minister headed up Glasgow Pride as it left Clyde Place, alongside Suki Wan, chair of the Scottish Youth Parliament.
Ms Sturgeon was named honorary grand marshal for the event in recognition of her long-standing support for LGBTI equality.
She said: "It's a real honour to be here leading the pride march
"Last year I became the first serving head of government in the UK to address a pride rally so when I got the invitation to lead the march this year I was very keen to do it.
"Pride marches are all about celebrating and affirming values that I think are important to many people across the country.
"Values like tolerance and respect and diversity and love and I think it's an appropriate thing for me as First Minister to be part of today and I'm proud to do so."
She said the values are important to the LGBTI community.
She added: "In many parts of the world these principles are under threat, more so now than they have been in my entire lifetime.
"So as First Minister of Scotland it's important for me to stand up for these principles and values."
Ms Sturgeon is the first serving prime minister or first minister in the UK to march at a pride event.
She was joined by a cross-party group of MSPs, including Green co-convener Patrick Harvie, Liberal Democrat Alex Cole-Hamilton, Conservative Jamie Greene and the SNP's Christina McKelvie.
Thousands of people, many carrying rainbow flags or holding placards, marched behind as the parade crossed the river and headed through the city to Kelvingrove Park.