Pilots, cabin crew and travel agents were protesting in England, Scotland, and Northern Ireland accusing their Governments of failing to restart travel by undermining the Covid-19 traffic light system.
With now major tourist destinations on the green list, which means people can travel quarantine free, the industry says it is on its knews.
Figures released for the 'Travel Day of Action' estimate that 195,000 travel jobs have been lost during the coronavirus pandemic or are at risk.
Among those who travelled to Westminster were Philippa Wilcox and Mark Johnson from the Oswestry-based Polkadot Travel and Claire Moore of Peakes Travel Elite, Shrewsbury.
Philippa said it had been an emotional day in London.
"To see so many people pulling together in our industry has been wonderful. But hearing people's stories and how they have been affected is quite heartbreaking," she said.
"It makes you realise just what an utter mess the situation we are in is. We need clarity from this Government on what our customers can expect this summer and how they are going to help the industry."
Claire Moore from Peakes said travel agencies hadn't been able to take full advantage of the Government’s furlough scheme.
“It has been a really tough 18 months in the travel sector. Our travel agency is classed as non-essential retail, so the shop has had to close over the lockdowns but during that time our customers have still needed our support which has meant a full team furlough was not an option for us. Our dedication to customer service is the foundation of our offering and we couldn’t compromise that. The team have needed to prioritise supporting our existing customers to re-arrange, refund and re-book holidays, through a period with severely reduced new bookings."
Transport Secretary Grant Shapps has expressed hope that "the world could open up", as holidaymakers eagerly await an update to the Government's foreign travel lists.
The Cabinet minister said other countries were catching up with the UK's coronavirus vaccination programme.
"Balancing the opening up whilst preserving people's safety and security at home is absolutely at the forefront.
"Of course I very much hope the world could open up. We've got to follow the data, and that's what we'll be doing in the meetings over the next few days."