The Plaza de Armas is the vibrant heart of Cusco, a sprawling square steeped in history. Originally the 'Huacaypata' or 'Warrior Square' for the Incas, it is now flanked by the magnificent Cusco Cathedral and the Church of the Compañía de Jesús. The central fountain, colonial arcades, and beautifully manicured gardens make it a perfect spot for people-watching, acclimatizing to the altitude, and soaking in the city's unique atmosphere. It serves as the main hub for festivals, parades, and daily life in Cusco.

Qorikancha, meaning 'Golden Courtyard' in Quechua, was the most important temple in the Inca Empire, dedicated to the sun god, Inti. Its walls were once covered in sheets of solid gold. After the Spanish conquest, the Convent of Santo Domingo was built atop the temple's foundations, creating a striking architectural fusion. Visitors can marvel at the incredibly precise Inca stonework, which has withstood centuries of earthquakes, juxtaposed against the Spanish colonial structure built around it.

Perched on a steep hill overlooking Cusco, Sacsayhuamán is an awe-inspiring Inca fortress and ceremonial complex. It is famous for its massive, zigzagging stone walls, constructed from enormous boulders weighing up to 200 tons, all fitted together with breathtaking precision without any mortar. The sheer scale of the site is staggering and offers panoramic views of the city below. It's a testament to the incredible engineering skills of the Inca civilization and the site of the annual Inti Raymi festival.

Known as the artisan's quarter, San Blas is Cusco's most picturesque neighborhood. Characterized by its steep, narrow cobblestone streets, white-washed adobe houses with blue balconies, and a bohemian atmosphere, it's a delight to explore on foot. The area is packed with independent art galleries, workshops of renowned local artists, and charming cafes and restaurants. At the top, the small Plaza de San Blas offers a lovely church with an intricately carved pulpit and a tranquil escape from the city bustle.

A visit to the Mercado Central de San Pedro is a true immersion into local Cusqueñan life. This bustling, vibrant market is a sensory overload in the best way possible. You'll find everything from colorful piles of fresh produce, exotic fruits, and countless varieties of potatoes and corn to shamanic stalls selling mysterious potions. Don't miss the food section, where you can sample authentic local dishes and fresh juices at incredibly low prices. It's the perfect place to shop for souvenirs like textiles and alpaca wool products.

Dominating the Plaza de Armas, the Cusco Cathedral (Cathedral Basilica of the Assumption of the Virgin) is a treasure trove of colonial art and architecture. Built over 100 years on the site of an Inca palace, it combines Renaissance, Baroque, and Gothic styles. Inside, you'll find hundreds of paintings from the Cusco School, intricate silver-covered altars, and the famous 'Last Supper' painting by Marcos Zapata, which features a guinea pig as the main course. Its sheer grandeur and historical significance make it a must-visit.

Located on the narrow Hatun Rumiyoc street just off the Plaza de Armas, the Twelve-Angled Stone is a perfect example of the Inca's mastery of stonemasonry. Part of a wall that once belonged to the palace of Inca Roca, this single diorite stone is famed for its twelve perfectly cut angles that fit snugly with the surrounding blocks. It symbolizes the incredible precision and skill of Inca engineers, who created seamless, mortar-less walls that have endured for centuries.

A short distance from Cusco, Q'enqo is a fascinating and mysterious archaeological complex. The name means 'labyrinth' or 'zigzag' in Quechua, which aptly describes the semi-circular amphitheater and the carved channels in its large limestone outcrop. It is believed to have been a holy place for ceremonies and rituals, possibly involving sacrifices and mummification. Visitors can explore the subterranean passages and admire the intricate carvings, which include representations of a puma, condor, and snake.

Known as the 'Red Fortress' due to the reddish hue of its rocks at twilight, Puka Pukara is a small Inca military ruin located on a hill with commanding views of the Cusco valley. It is believed to have served as a guard post or checkpoint to control the flow of people and goods into Cusco and the Sacred Valley. The complex includes large walls, terraces, and staircases, and its strategic location makes it an interesting stop when exploring the archaeological sites just outside the city.

Often referred to as the 'Inca Baths' or 'Baño del Inca', Tambomachay is an archaeological site renowned for its sophisticated water channels, aqueducts, and waterfalls, all meticulously carved from stone. This serene site was likely a spa for the Incan elite or a temple dedicated to the worship of water, a vital element in Inca cosmology. The continuous flow of fresh spring water through the fountains is a marvel of ancient hydraulic engineering and offers a peaceful and refreshing visit.