With its pleasant turn-of-the-century houses, Ruse on the Danube is one of the best places to visit in Bulgaria. But if you brave the heavy traffic on the busy and narrow road to Ruse, do not terminate in the city.

Ruse's surroundings are an excellent opportunity for a day trip, especially in spring when everything is green, blooming and buzzing under the balmy sun. Most of these sights are scattered around the winding course of the Rusenski Lom river and its confluents, Cherni Lom and Beli Lom.

About 20 km from Ruse, the bends of the Rusenski Lom are home to about a dozen churches and monastic cells carved into the rock. In the 12th-14th centuries they formed a single monastery, which in its heyday was the home of up to 800 monks. The popularity of the Ivanovo monastery was based on its endorsement of the hottest spiritual trend of the time: Hesychasm. Born in Byzantium, it spread rapidly throughout the Balkans. It was a mystical tradition that promoted silence and meditation in solitude as the shortest path to salvation.

Medieval murals from the UNESCO-listed Ivanovo rock churches

Ivanovo's rock churches were richly decorated with murals, some of which have survived to the present day. This, along with the monastery's historical significance, is why the site is on UNESCO's World Heritage List.

As a bonus, the Ivanovo Rock Churches are part of the Rusenski Lom Nature Park. Covering over 8,000 acres, it is a place of greenery, rock formations and flowing water, home to a number of rare and endangered species.

A contrast to the melancholic experience of walking among the weathered medieval faces of Ivanovo is a visit to the nearby rock monastery, by the village of Basarbovo. The St Demetrius of Basarbovo Monastery is polished, over-manicured and bustling with tourists.

A few kilometres from Ruse, on one of the steep meanders of the Cherni (Black) Lom River, lies Cherven, one of Bulgaria's most interesting and authentic fortresses. Its most spectacular element is a three-storey defence tower.

The Cherven Tower may look familiar to you, and with good reason. In the 1930s it was used as a model for the reconstruction of the almost completely demolished Baldwin Tower on Tsarevets Hill in Veliko Tarnovo.

The Cherven fortress is the descendant of an ancient Thracian settlement which the Byzantines fortified in the 6th century in their energetic but ultimately unsuccessful attempt to prevent the Barbarians from crossing the Danube and raiding their territories. Eventually the barbarians prevailed. When the Proto-Bulgarians settled in the region in the late 7th century, they also took over Cherven.

If you think you have seen this tower somewhere before, you are not wrong. Architects used it as a model when they rebuilt the famous Baldwin Tower on Tsarevets Hill in Veliko Tarnovo

In the 12th-14th centuries, Cherven was an important military, administrative and economic centre.

It was a true medieval town, with fortified walls and massive towers – home to merchants and craftsmen, soldiers, clergy and officials. The local lords lived in a walled palace, second only to that of the Bulgarian kings in the capital, Tarnovo. In 1235 Cherven became a bishopric. This tradition lives on – even today the title of the bishop who resides in Silistra includes Cherven.

When the Ottomans took over Cherven in 1388, they appreciated its strategic position. The town remained an administrative centre of the empire for several centuries.

Gradually, however, trade on the Danube became more important, and the town of Rustchuk (now Ruse) began to take shape near Cherven. Eventually the fortress was abandoned.

In the 2000s, the village of Nisovo, on the banks of the Beli Lom River, became the centre of a public furore. This was caused by media reports that it had a mysterious cemetery, where Templars were buried. The gravestones, it was claimed, were in the shape of a Maltese cross, the symbol of the Order of the Temple. This was taken as proof that some of the knights had survived the infamous and bloody end of their order in 1307 and found refuge in Bulgaria.

This abandoned cemetery near the village of Nisovo got suddenly famous for its unusual crosses

The truth about the old cemetery in Nisovo is quite different. For generations, the locals have known it as the burial ground for plague victims. Indeed, in the past people often fled plague-infested villages to start a new life in a "clean" place.

There is also an explanation for the "strange" shape of the tombstones. Cemeteries with stone crosses and gravestones were actually common in Bulgaria and throughout the Balkans between the 17th and early 20th centuries. Most of them are now lost, but some have survived, often hidden under thick undergrowth and completely forgotten.

Different types of gravestones were associated with different regions, with designs spread by itinerant stonemasons. The "Maltese" cross is most common in the Ruse area and northwest Bulgaria. As a symbol, however, it is much older than both the Knight Templars and the old cemetery at Nisovo. The Maltese cross has appeared on ritual and everyday objects in the Balkans and the Mediterranean since prehistoric times, and is interpreted as a symbolic representation of the sun.

According to locals, mythical hero Krali Marko used to play with this oddly-shaped rock by Mechka village

In Mechka, a village south-west of Ruse, on the banks of the Danube, there are two stone pillars, 2.5 and 12 metres high. They probably date from the Mesozoic era, when dinosaurs roamed the earth. For the local Bulgarians, however, these formidable rocks are associated with the mythical hero Krali Marko. In a show of strength, he is said to have lifted the larger of the two rocks with the tip of his finger.