The Palacio Real de Madrid — the official residence of the Spanish royal family in the city — is Europe's largest royal palace, boasting a whopping surface area of 135,000 square meters and a staggering 3,418 rooms. This architectural marvel is not only visually stunning, but also features spectacular outdoor gardens and exquisite frescoes, furnishings, and paintings within its walls. Originally constructed in 1764 as a replacement for the Alcázar castle, which had been destroyed by fire three decades earlier, this magnificent edifice is a must-see attraction for visitors to Madrid. Nearly the entire palace is open to the public, including the Armoury and Pharmacy.

Madrid's three major art galleries are all within a short walk of each other, and together they make up a magnificent display illuminating the history of Western art. Each one of the galleries is so large that seeing everything in one day seems an impossible task. Luckily, your ticket is valid for a year, and you are free to dip in and out of each museum as much as you please.

One of Nha Trang's most alluring attractions is the Po Nagar Cham Towers, an actively used site of religious significance to Cham, Chinese and Vietnamese Buddhists; only 4 towers remain standing (researchers speculate there may have originally been up to 10). Constructed between the 7th and 12th centuries, the towers have a history that goes back to as early as the 2nd century AD when the location was first used for religious purposes. The complex teems with worshippers and visitors daily – you'll likely see some dozing on the hillside, others having a family picnic, and others yet enjoying a stylised performance at the on-site outdoor stage.

Casa de Campo, the largest and most significant public park in Madrid, was once a Royal Forest and is now open to the public. The park boasts many attractions, including the Madrid Zoo, an amusement park, a Teleférico (cable car), and a lake. In addition, the park is a popular spot for outdoor activities such as working out and swimming during the summer. Escape the hustle and bustle of the city and enjoy over 1.5 hectares of natural surroundings before returning to the vibrant city.