In the distance, a waterfall. Olaf hikes up to it, over a few hours. It is truly beautiful. He stops and sits on a rock to eat some nuts and drink some water, enjoying the panorama and making little notes in his diary. Then, he reshoulders his knapsack and continues on.

A little trail takes him behind the waterfall. Clinging to the rockface, he inches along. The rocks aren't that slippery, but he wants to be safe if they are.

Somewhere behind the waterfall, there's a crack that he easily fits into. After producing an electric torch, he cautiously moves into the cave.

There! A glint of torchlight reflects back from deeper in the cave. Treasure, perhaps? He allows himself a thrill of boyish excitement.

It's not treasure. It's a mirror, as big as he is, perfectly reflective. It has no frame, but is set into the cave-wall. It seems impossible, and yet, here it is. He reaches out to touch it-

-and his hand goes through the mirror.

Incredible. What sort of trick of the light or air could cause this? Olaf looks back. The path behind him is clear. What to do next is obvious. Olaf steps through the mirror...

...and out into a lively town square, an open space formed where two cobbled streets cross. There's daylight above him, a low hum of chatter all around, and well-worn cobblestones under his feet where a moment ago there was the uneven floor of the cave. The buildings around the square, and the ones he can see down the cross-streets, are mostly timber-framed with thatched roofs. A horse-drawn cart crosses right in front of him in a noisy clatter. 

The square is busy enough that nobody seems to have noticed Olaf appearing out of nowhere. He's landed in one corner of the square, next to a stone building. The wooden sign hanging over the door has a stack of coins painted on it. 

What?

Olaf is fairly certain that this isn't a town physically hidden behind the cave. The people look different. The air tastes different. And when he steps backwards, he presses against a very solid, very un-mirror-like wall.

This is certainly an adventure. Olaf might be in some sort of vision, but he's taken a few exotic substances and participated in a few related rituals in his travels, and this doesn't feel like them. This is a solid world, a real one, one he slipped into with no warning.

His clothes seem to blend in fairly well. For any given climate, there are only so many reasonable ways to design rugged adventuring gear. Olaf begins wandering the streets, listening to the people speaking, getting a feel for the rhythms of this strange town.

The people around him are wearing clothes that look somewhat old-fashioned to Olaf's eyes. This whole scene—buildings, people, horses and carts and all—looks like it could be from two hundred years ago, but could just as easily be from a rural backwater European town that doesn't have electricity yet, and he's visited plenty of those in his time. 

However, a few details stick out as odd. 

1. Maybe one person in three has hair of purple, blue, bright red, or some other unnatural colour. 

2. That man coming out of the tavern, on the other side of the square, is dressed in robes, and with him is a woman in full plate armour of a style that hasn't been worn by men in centuries. 

3. There's a strange small furry creature with big ears, sitting on a tree-stump and talking to people. 

Odd indeed. And amazing. Some people, at this point, would start to worry about being stranded, in an unfamiliar town that appears to be not wholly of his world. Olaf isn't worried. He'll make it home eventually. He always does.

He would dearly like to speak to the small furry creature, but he isn't quite sure what he'd say. "Hello, you don't appear human, please tell me about your race" is not a very polite way to start a conversation.

Aha. A tavern. They might call it an ale-house, inn, bar, motel, hole-in-the-wall, hostel, or monastery, but every town has at least one: a place to relax, to sit down, to converse over a drink and a bite to eat. Olaf walks in the door, taking a look around.

Like the town around it, the tavern is a quaint, cosy little place that looks like it could be from any time in the last few hundred years. The smell of freshly-baked bread wafts through the air as Olaf enters. This being the middle of the day, the place isn't heaving, but there are a few people hanging around chatting, including more folks in armour of varying styles. 

A blonde woman in a flour-dusted apron greets Olaf with a warm smile. "Welcome to the inn! I'm Serenity. Can I get you something to eat or drink?" 

Olaf looks around curiously. He's fairly certain that even when plate armour was in common use, it wasn't commonly worn when there wasn't a battle going on. Do they expect violence to erupt at any moment? He unconsciously puts a hand to his inner coat-pocket, feeling the outline of his revolver. The heroes in his books are all much better shots than he is, of course (except the ones which are too heroic to even use guns). But the people here seem relaxed, so the armour's hopefully just a cultural thing.

"Thank you, Serenity. I'd love something, but I'm not sure if I can pay for it. What currency do you accept here?"

He feels for his purse. Fortunately, he's carrying quite a bit of cash, since there wasn't a trustworthy safe where he was staying. He has five pounds sterling in one-pound notes, four one-shilling coins, tuppence, three US silver dollars and five three-cent nickels, six 25-cent Dominion shinplasters, and, of course, the one-hundred-convertible-guilder note he acquired in the Independent Protectorate of Analdi-Wat and keeps as a lucky charm.

This question flusters her a bit. "...oh dear, I'm not sure what I'm supposed do with foreign coins. I'm sorry, I haven't been doing this very long. You might have to ask at the bank? But I'm happy to feed you a meal first, and you can pay me later once you've figured it out." 

"Very generous of you." Olaf smiles appreciatively, and feels a little bad for being so nervous about the armour. "Could I please have a bowl of soup, then?"

"Of course! Would you like some bread with it? I just baked a fresh loaf." 

"That would be lovely. How much will I owe you?"

"Well, in the local coin I'd say four coppers. I can show you some, if you want to compare them to yours?" She starts rummaging in her belt pouch. 

Olaf takes out his diary, and writes Tavern - 4 copper debt in small, neat letters.

"Please", he says with a curious nod. 

Serenity pulls out a handful of coins. They're thin metal discs, mostly copper and silver, with a smaller number of gold ones. The gold coins are slightly smaller than the silver, which are in turn slightly smaller than the copper; each metal seems to only come in one size.

She hands him a copper coin to inspect. It's about an inch in diameter, and looks like it was stamped out from a thin sheet of copper, rather than cast in a mold. The stamped design, which has a dragon's head on one side and an oak leaf on the other, is very slightly off-centre.

Olaf looks it over, feeling the weight, running a finger over the dragon. It's not any currency he's seen or heard of before, and he's seen most of them. The dragon's head is unusual. Perhaps it's a heraldic element? This place does seem to be almost medieval in some ways.

"Thank you." He hands it back, and settles into casual conversation. "You said you're new here. What brought you to this work?"