In 1871, Pavel von Derwies built the luxurious estate "Castle Trevano" in the Italian part of Switzerland, on a hill in Lugano, in the village of Trevano. In summer and autumn, he moved there with his family. Rumor had it that the baron was not a model family man and built the castle during an affair with Countess Maria Ivanovna Keller.

The construction was carried out by Swiss architects popular in Russia at that time: Francesco Botta, Bernard Simon, Giuseppe Bernardazzi, Bernardino Maraini, as well as sculptor Vincenzo Vela.

The castle in Trevano became a true marvel and one of the most luxurious estates in Switzerland. It was surrounded by gardens illuminated by 400 gas lamps, with grottos, mazes, fountains, and pools with exotic fish, as well as exotic plants.

L. I. Avtonomova, the wife of a priest from Nice and Lugano, described the Trevano park in her book "Memoirs of the Life of Protopresbyter I. V. Vasiliev": "The park occupied several desyatins; there was a greenhouse with a pool for Victoria Regia, whose pink flowers reached enormous sizes and wilted on the third day. Thousands were spent for those three days! At the end of the park, there was a farm, and they didn't know what to do with the milk... An alley lined with rhododendrons and acacia led to the house, from the flowers of which pancakes were made. In the park, there was an alley with a woven gazebo, over which the Isabella grape twined, which we secretly ate. On the slopes of the mountains were vineyards, from which wine was made..."

The central estate was designed in the style of an ancient Roman villa with a crystal dome, a marble staircase, and a balustrade made of Bohemian crystal. Inside were Roman baths, sculptures, tapestries, frescoes, and paintings.

Here stood a statue of Spartacus by Vincenzo Vela, now adorning the town hall of Lugano. It was a true temple of the arts. The left wing of the castle housed a theater with 16th-century tapestries, next to it was a concert hall decorated with silver and gold, featuring an organ and two Steinway pianos.

Pavel von Derwies, having left business and court life, dedicated himself to music. According to Avtonomova's memories, "he was a wonderful musician, played with soul, and even composed music."

The baron maintained a personal orchestra, and performances in the castle became important cultural events for Lugano and Ticino. He personally selected the music, financed productions, and supported the orchestra and singers. The theater featured German, Italian, Russian music, and works by the baron himself.

Unfortunately, his life was tragically cut short in 1881 when his 16-year-old daughter Varvara died after falling from a horse. Accompanying his daughter's coffin, Pavel von Derwies died of a broken heart, although there were rumors of suicide.

The last time von Derwies's music was heard in Lugano was at the funeral service in the Orthodox church of the castle, where the funeral march of his composition was performed. His son Sergey Pavlovich von Derwies did not like the castle, and soon the estate was sold. The family no longer appeared in Lugano.

Castle Trevano changed many owners and fell into disrepair after World War II. Local authorities decided to demolish the old buildings and construct a modern educational institution in their place.

In 1961, the castle was blown up, and only dust remained from its former glory. However, the vineyards and some buildings have survived to this day, reminding of Russian dachas and Swiss chalets.