Mermaids in folklore use their charms to lure sailors on to the rocks but the Mermaid pub has a more benign role: to draw customers in with a good range of beer in a friendly atmosphere.

It’s quite a range. If you like real ale, there are half-a-dozen handpumps with an ever-changing programme of beers from small craft breweries.

If you enjoy Belgian beer, then there are 28 on offer. And for cider drinkers, there are12 to choose from – and these are proper ciders from small farm producers, not fizzy fruit drinks served “over ice”.

The Mermaid, at 98 Hatfield Road, is run by a young couple in their 20s, Emily Taylor and Luke Lovell. They are both from Rugby. Emily, who took over the Mermaid a year ago, had worked as a bar supervisor and a chef. Luke has no previous pub experience but, continuing the aquatic theme, has taken to the Mermaid like a duck to water.

The pub dates from the 19th Century when it was surrounded by fields. It was an “ale house” mainly for farm workers but, observing the social graces of the time, it had two bars that enabled the better-off to avoid men in working clothes.

The Mermaid was long ago knocked through into one spacious dog-legged room, dominated by its large L-shaped bar. The floors are scrubbed wood, there’s a darts area at one end, and plenty of tables and chairs for customers.

As befits a pub from the Victorian age, it’s decked out with fascinating memorabilia from breweries of yesteryear. You can spot signs and mirrors for Royston Fine Ales, Hammerton Oatmeal Stout, Barclay Perkins London Stout, Fremlins and Tamplins among many others.

The Mermaid, when I first knew it back in the 1970s, was a Whitbread pub. That was not unusual in St Albans, as the national brewery group had taken over Greens of Luton and its substantial estate of pubs in the area. When Whitbread left brewing in 2000 the pub was briefly run by a large Leicester brewery, Everards, but that association didn’t work, and the Mermaid is now part of a small group called Burlison Inns, which owns six pubs in the area.

Burlison specialises in serving beers from craft breweries. The only regular is Citra, from Oakham Ales in Peterborough, and it’s a sign of the changing times that a beer that would have been considered too hoppy for taste a few years ago is now so popular that it can’t be taken off the bar. It takes its name from an American variety of hop that gives a big blast of bitterness and citrus fruit.

Other beers on offer when I dropped in included Gundog Booze Hound all the way from Northumberland, Nethergate Hogwash from the Essex/Suffolk border, Purity Pure Gold from Warwickshire and Hook Norton Mild from Oxfordshire.

Emily says the house policy is to have a wide range of beers, from a dark mild such as Hook Norton, through golden ales, traditional bitters to black stouts. A large board announces beers that will soon be available, including Titanic Stout from Stoke-on-Trent, Tring Brewery’s winter ale, two Yorkshire ales, Rudgate Battle Axe and Salamander Scuttlebutt, Monty’s Sunshine from Powys and a new golden ale from Hook Norton called Lion.

If nothing else, the choice proves that today’s breed of brewers have no shortage of imagination when it comes to naming their beers. The age of “mild” and “bitter” is as out-dated as a two-bar pub.

As a lover of the amazing beers of Belgium, I was delighted to see the big range available in the Mermaid. You can sample the delights of beers brewed by Trappist monks at the monasteries of Chimay, Orval and Westmalle, along with the legendary golden ale Duvel – the name means Devil in Flemish – and the dauntingly-named Mort Subite, which stands for Sudden Death: it takes its name from a card game played in bars in Brussels.

There will be even more on March 5, which will be Belgian Beer Day at the pub. Book a cab.

Emily and Luke offer simple, unpretentious food – “we’re not gastro,” she says firmly. There’s one hot dish of the day, such as beef in ale stew, along with pies and other snacks.

There’s also live music every Wednesday evening at 8pm when the pub is full to bursting. Emily will no doubt encourage regulars to join her in August when she plans a charity cycle ride to Brussels to raise money for Grove House.

Her policy at the Mermaid, which is working well, is as simple as the food: “good ale for local people”. It also comes with a good sense of humour. A notice at the door offers a “man crèche” and suggests that wives or partners should deposit the male of the relationship while they go into the city centre.

The Mermaid lives up to its legend.

*Follow Roger on Twitter @RogerProtzBeer. He edits the CAMRA Good Beer Guide.