The Hotel Viminale feels like a comfortable, standard small Roman hotel, decorated in a faux-antique style with gilded decor and classical art. The picturesque Art Nouveau building mimics older styles in its architecture. The lobby is decorated with 19th-century-inspired style, with soaring arched ceilings, green carpeting, cream antique-inspired settees, and tapestries on the walls. The next room houses a lounge area, home to the small house bar, a gaudy space with high beamed ceilings, large windows, green couches, ornate mirrors, a fireplace, and a wood cabinet of spirits. The small breakfast room is decorated with ornate moldings, classical still-life artwork, and wooden chairs at tablecloth-covered tables. The roof garden offers a quiet respite from the city, outfitted with tan wicker seating and glass-topped tables surrounded by potted plants. The two higher-floor roof terraces have panoramic views over the city, as well as black wicker chairs and potted plants. Some guests complain, though, that the couches in the lounge are worn and tired, and that the hotel needs to be cleaned better.

The Hotel Viminale is located in the oldest archaeological area of Rome, around the corner from the Basilica of Santa Maria Maggiore. The Rome Opera House, Roma Termini train station, Piazza della Repubblica, and the Trevi Fountain are all also within a five-minute walk. Santa Potenziana, the Palazzo Barberini, many restaurants, and plenty of public transportation options are also walkable. Both the Leonardo da Vinci International Airport and the Ciampino Airport are a 30-minute drive away, though the hotel offers no parking.

The classical, traditional rooms at the Hotel Viminale are decorated in a gilded, 19th-century-inspired style, with gold bedspreads, padded headboards, striped tan wallpaper, and hardwood floors. Crown moldings accentuate the aesthetic, and wooden chairs provide extra seating. All rooms have air-conditioning, safes, minibars, flat-screen TVs, and coffeemakers. Pale pink bathrooms have heated towel racks, hairdryers, and pink tiled showers, along with signature toiletries; the bathrooms are slightly dated, only have showers, and lack counter space. It's worth noting that many guests complain that rooms are dusty and need a deep-clean.

An adequate breakfast buffet is included in all rates at the Hotel Viminale and includes meats, breads, cheeses, cakes, fruit, coffee, pastries, eggs, and yogurt. Cocktails and drinks are available in the lobby lounge area, which also has a small Internet corner. Wi-Fi is free throughout. The hotel's highlight is the outdoor roof garden and two roof terraces overlooking the city; all three are outfitted with seating and eating areas. Concierge services are available, and there is a basic fitness center. On-site parking isn't available.