Turkey bridges Europe and Asia. Istanbul, its largest city and commercial center, straddles the strategic Bosphorus Strait. Part of the city is in Europe, and part in Asia. The Golden Horn inlet divides the new town — with its high energy business zones — from the old town — where you’ll find the major sights.

As a city which is over 90 percent Muslim, Istanbul offers a good opportunity to better understand Islam. Visitors are welcome to visit historic mosques and at the same time, experience a religion that still packs the house.

The Blue Mosque was the 17th-century triumph of Sultan Ahmet I. Architecturally, with its six minarets, it rivaled the great mosque in Mecca — the holiest in all Islam.

Its grand courtyard welcomes the crowd that gathers for worship.

As with all mosques, you park your shoes at the door and women cover their heads. If they don't have a scarf, there are loaners at the door.

Countless beautiful tiles fill the interior with exquisite floral and geometric motifs. It's nicknamed the Blue Mosque because of its blue tiles. Blue is a popular color in Turkey. It impressed early French visitors enough for them to call it "the color of the Turks"… or turquoise.

While churches portray people like this, Muslims believe the portrayal of people in places of worship draws attention away from worshipping Allah as the one God. In mosques, rather than saints and prophets, you'll see geometrical designs and calligraphy. This explains why, historically, the Muslim world excelled at non-figurative art, while artists from Christian Europe focused on painting and sculpture of the human form.

Artful Arabic calligraphy generally shows excerpts from the Quran and quotes from Muhammad. As a church would have Jesus and God front and center, in a mosque, elaborate signature medallions high above the prayer niche say "Muhammad" and "Allah."

Large ceremonial candles flank the mihrab — that’s the niche that points southeast to Mecca, in Saudi Arabia — where all Muslims face when they worship.

Services are segregated by gender: The main hall is reserved for men, while the women's section is in the back. While to some it's demeaning to make women stay in back, Muslims see it as a practical matter. Women would rather have the option of performing the physical act of praying in private.

Like churches have bell towers, mosques have minarets. According to Muslim tradition, the imam, or prayer leader, would climb to the top of a minaret to call the faithful to prayer. These days, the prayer leader still performs the call to prayer live, but it's amplified by loudspeakers at the top of the minarets.

[Call to prayer.]

The call is always the same: Allahu Akbar… God is great, witness there is only one God. Muhammad is his prophet. Come join the prayer. Come join the salvation. When this happens, practicing Muslims drop into a mosque, face Mecca, and pray to God… then after a short service praising God, workaday life resumes.

Modern Turkish culture is complex. To sort it out properly, I'm joined by my Turkish friend Lale Surmen Aran, who co-authors my Istanbul guidebook.

Rick: So what does the call to prayer mean to you?
Lale: That's personal thing. Most of these people you see here are probably Muslims, but Turkey is a secular country; it's in our constitution. But on the other hand, we say that you never know who has got the money or the faith. The real virtue is not to show if off.

Turks love to meet and mingle at Ortaköy — just under the massive bridge that connected Europe with Asia in 1973. The tempo of life in Turkey, like other Mediterranean lands, is slow enough to enjoy the moment and good friends. People love their tea… the sound of dice on the backgammon board… and sucking on the hookah, or nargile; generally a tobacco-free dried fruit smoke.

This city, so layered with rich history, was officially named "Istanbul" only in 1923 with the foundation of the modern Turkish Republic. Before that it was called "Constantinople."

Over the centuries, this city has been the capital of two grand empires. The Byzantine Empire started in the fourth century and lasted until the 15th century — that’s when the Ottomans took over, and ruled until the end of World War I. Today, even though Turkey is governed from Ankara, Istanbul remains the financial, cultural, and historic center of the country.

As ancient Rome was falling, Emperor Constantine moved the capital from the west here to the less chaotic east in around AD 324. It was named Constantinople in his honor.

Then, in 476, Rome and the Western Empire fell to invading Barbarians. That left Constantinople the leading city of Western Civilization.

Traces of the Roman capital can still be found. This square was a racetrack, like the Circus Maximus in Rome. Built in the fourth century to seat over 60,000 fans, the Hippodrome was Constantinople's primary venue for chariot races.

Its centerpiece, this 3,500-year-old ancient Egyptian obelisk, was originally carved to honor a pharaoh. It was moved here to ornament the racetrack in the fourth century. What you see today is only the upper third of the original massive stone tower.