Caroline Powley, 31, was in Edinburgh on a surprise birthday treat for her fiance.

The Kent-based veterinary nurse and her partner, business analyst Neil Dave, planned to visit another tourist attraction but found out it was closed on Tuesdays.

They decided to nip to the nearby Scottish Parliament instead, and discovered they were landmark visitors.

Ms Powley, from Paddock Wood, agreed that she was an accidental visitor to the building, but said: "We're more than happy to come in here and have a look round, it's a lovely building."

She said she never expected to be treated as such an honoured guest.

"It was a complete surprise for both of us coming in here today," she said.

Speaking in the Parliament's chamber, she said: "We've been lucky enough to come in here and see in this room and it's a lovely airy building. It's beautiful.

"I think Scotland's a beautiful place. Edinburgh itself is just wonderful, very welcoming."

Mr Dave said: "It was my 30th birthday last week, so it's a complete surprise and a surprise trip up here from Caroline.

"We attempted to go next door but it was closed, so we landed up coming in here."

Presiding Officer Alex Fergusson presented Ms Powley with a silver plate to mark the occasion.

"To have reached such a significant milestone of two million visitors to Holyrood in our 10th anniversary year is particularly pleasing," he said.

"The Scottish Parliament has always worked hard to open its doors to all and I truly believe that it is our record of seeking to engage with the people of Scotland that has been one of, if not the, greatest achievement of Holyrood to date."

Ms Powley is the two-millionth visitor to the Holyrood building since it was officially opened in 2004.

The total number of visitors to the Scottish Parliament since its creation in 1999 is nearly 2.5 million, equivalent to about half of Scotland's population.

Schoolgirl Eilidh Willis, 11, was named the one-millionth visitor to the Holyrood building in March 2007.