Tilda realizes she has given just enough information to be cryptic. She wants to say more, to explain, but how can she? How can she tell this sensible person that she is chasing the identity of some ghosts?

‘I mean,’ she tries, ‘I imagine they would have a boat.’ This still sounds lame, so she adds, ‘I saw a picture once, of a woman, and two men, in a boat. There was a Celtic feel about it. The woman was … striking. Like a warrior, or someone powerful, anyway, but not dressed in finery. More … earthy, somehow. She had tattoos.’

The professor waits for more.

Tilda shrugs. ‘I thought I could use patterns like that in my work. I just wanted to get the context right.’ She turns back to the map. ‘There would have been other buildings here centuries before this, wouldn’t there? Different ones, of course.’

‘Well, if you’re talking about the Celtic people, yes. Nothing that remains now. That’s the trouble with huts built of sticks or wattle, they don’t leave much for we historians to work with.’ He comes to stand next to her. ‘We know now that there were people living around the lake before the Romans came here, and long after they left, naturally. It’s a good place for a settlement. There were monks and villagers here, and even royalty, such was the appeal of the place. I think I mentioned Prince Brynach to you on your previous visit. He went to all the trouble of building the crannog here precisely because he recognized what a splendid place to live the lake provided.’

‘There are just a few trees left on the island now. Was there really a palace there once?’

‘Not one you and I might recognize as such, but yes. It was a royal dwelling, built to impress. It was known as the long hall, or sometimes the great hall—a simple construction, timber framed, with wattle and daub. We are not entirely sure what materials were used for the roof, most likely some sort of reed thatch from the lake. The large space inside could accommodate gatherings and meetings as well as providing a relatively warm and comfortable home for the prince.’

‘It must have been cold, surely? On the water like that. When it was misty or frozen, wasn’t it damp and horrible?’

‘There is evidence they used a large fire in the center, and later another at the far end, though this was before the idea of fireplaces set into the walls with proper chimneys. They would have had to dress against the cold.’ He smiles, ‘Don’t forget how much heat people themselves generate, all in one space together. And there would have been more people living around the lake. They could have retreated to the crannog for safety if the settlement came under attack.’

‘And did it?’