Night location: Istanbul, Turkey

Today we have seen many of the major sites of Istanbul. Our hotel is in a brilliant location as it is an easy walk to most of the tourist attractions. Under the instruction of Tennille and Robby, we were at the Topkapi Palace at 9am so we were able to enjoy walking up the grand promenade practically by ourselves. The palace was constructed between 1460 and 1478 following the conquest of Constantinople. It covers approximately 7000 square meters and served as the official residence and centre of administration for the Ottoman sultans until the mid 19th century.

We went straight to the Harem and were fortunate to have the entire place to ourselves. These rooms were the private apartments of the sultans, their wives, concubines and children, and black eunuchs who acted as guards for the women. Complete with multiple bath complexes, kitchens and small mosques, these rooms were elaborately decorated with entire walls of hand painted ceramic tiles, mother of pearl inlaid doors, marble water features, colourful carpets, stained glass windows and beautiful domed ceilings.

Kiosks or meeting halls were dotted around the grounds, each built for a different purpose by various sultans. The Imperial Council Hall was impressive with its intricate entry doors and large cushioned benches, but the small library was our favourite. Built in the 18th century and decorated with beautiful hand painted tiles, stained glass windows and a gilded ceiling, reading stands in front of comfortable window seats with the sun streaming in made this space feel particularly inviting. Above the door an inscription read: 'My friend take learning seriously and declare, "O my Lord, increase me in knowledge."'

The palace grounds were a pleasure to walk through as there were huge garden beds of sweet smelling roses and large trees provided plenty of shaded spots to rest. David was particularly impressed with the manicured lawn that Lily would have loved to roll on, and then dig up. Arched porticoes wound around the buildings leading to balconies with views over the gardens, water features or the Bosphorus and the city skyline.

Within the palace complex are the Archaeological museums of Istanbul. Of particular note was the Kadesh Treaty of 1269 BCE which is the first known peace treaty in the world. Written in Akkadian, the international language of the day, it outlines the concluded negotiation of Ramases II and the Hittite king Huttusilis and the plan to no longer fight each other, and to also send help if either nation was attacked. In addition to this, the museum housed an impressive collection of Sarcophagi, the most famous being the Alexander Sarcophagus belonging to the last king of Sidon and depicting impressive battle scenes of Alexander the Great.

From the palace grounds we visited the tombs of the Sultans which required Amber to put on her head scarf and for us both to remove our shoes before entering the five pavilions. The tombs lie just behind the Hagia Sophia so we went straight there and were pleased to be able to walk past the large queue of people standing in the sun due to our epic Museum pass.

The Hagia Sophia has a fascinating history. Built in the 6th century CE under the direction of Byzantine emperor Justinian I it served as the main cathedral of Constantinople for over a millennium. There are three aisles separated by columns and a wide gallery above that can be accessed by a ramp similar to what can be seen in sports stadiums today. After the Ottoman conquest in 1493 it was repurposed into a mosque by removing the bells and destroying or plastering over Christian mosaics. Minarets were added and huge circular murals of Arabic calligraphy dominated the support pillars. In 1934 the building was secularised and is now labelled a museum.

Various mosaic panels that have been restored date from the 10th century and offer valuable insights into the changing religious iconography from this era. One panel that was high above a doorway displayed the Virgin Mary being gifted a model of the city from the Emperor Constantine and a model of Hagia Sophia from the Emperor Justinian I. Due to its historic value, it was absolute chaos inside with loads of tour groups being led with umbrellas or flags and people posing for photo after photo. We reflected that this site was evidence that a church is more than just a building as there seemed to be no sense of the divine in this cavernous space.

Our final stop on our tour was the Basilica Cistern. Commissioned by Justinian I in 532 CE, the cistern features a forest of 336 marble and granite columns that were repurposed from ruined temples for this project. The capitals at the top of the columns vary from the plain doric style to the more elaborate corinthian style. It is able to store up to 80,000 cubic metres of water which was delivered via 20 kilometres of aqueducts from a reservoir near the Black Sea. When the Byzantine emperors relocated, it was forgotten by the city authorities, and it wasn't until 1545, well into Ottoman rule, that it was rediscovered due to rumours that locals were able to draw water and catch fish from access holes in their basement floors.

During the cleaning process in 1985 two colossal heads of Medusa were found to be the supports for two columns in order to increase their height to match the others. The origin of these heads is unknown but their discovery goes to show the recycling efforts of the ancient Byzantines.

The space was dimly lit and it had been drained so only small puddles could be seen in the orange glow, but it was certainly atmospheric. It seems hard to believe that this was built with the understanding that no one would ever see it or appreciate it for its aesthetic value. Visiting it today has made Amber really want to rewatch the James Bond classic 'From Russia With Love'.

To conclude our massive day we enjoyed dinner on a ninth floor restaurant terrace that offered spectacular views of the city skyline. Positioned directly opposite the Blue Mosque, we could see right across the Hagia Sophia to the Bosphorus and the Galata Bridge. The evening prayers rang out from the minaret as we were served our meal.