Hi,
I know you won’t use this but here’s roughly how you should be doing it.
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<title>Santo Domingo Sightseeing</title>
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<div id="Santo-Domingo" class="cityTimeDate"></div>
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<h1 id="att0">Santo Domingo</h1>
<p>Dominican Republic</p>
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<li><a href="#att0">Zona Colonial</a></li>
<li><a href="#att1">Malecon</a></li>
<li class="noborder"><a href="#att2">Columbus Lighthouse</a></li>
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<li><a href="#att3">Mirador Park</a></li>
<li><a href="#att4">Three Eyes</a></li>
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<h5>Major Attractions:</h5>
<div class="dest">
<ul>
<li><a href="#att1">MALECON</a></li>
<li><a href="#att2">COLUMBUS LIGHTHOUSE</a></li>
<li><a href="#att3">PARQUE MIRADOR SUR</a></li>
<li><a href="#att4">LOS TRES OJOS</a></li>
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<h5>See other destinations:</h5>
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<li><a href="/Asia/Indonesia/indonesia.php">JAKARTA</a></li>
<li><a href="/Asia/Indonesia/bali.php">BALI</a></li>
<li><a href="/Europe/Spain/Barcelona.html">BARCELONA</a></li>
<li><a href="/Americas/DomRepublic/StoDomingo.php">SANTO DOMINGO</a></li>
<li><a href="/Americas/DomRepublic/Punta.php">PUNTA CANA</a></li>
<li><a href="/Oceania/Australia/Sydney.html">SYDNEY</a></li>
<li><a href="/Asia/India/India.php">INDIA</a></li>
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<li><a href="/">HOME PAGE</a></li>
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<p> Hotel chains that guarantee the lowest Internet rates.</p>
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<h5>You book with them,<br>
not with us.</h5>
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<P style="font-size: 12pt; font-family: Tahoma; color: black">Click the logos below to enter the hotels' own websites.</p>
<a href="http://www.tkqlhce.com/click-7089264-10577445" target="_blank" onmouseover="window.status='http://www.Marriott.com; http://www.gomarriottvacations.com; http://www.ShopMarriott.com';return true;" onmouseout="window.status=' ';return true;"> <img src="http://www.lduhtrp.net/image-7089264-10577445" width="120" height="60" alt="Courtyard by Marriott - Make the most of your stay!" ></a> <a href="http://tc.tradetracker.net/?c=5516&m=12&a=143420&u=https%3A%2F%2Fwww.occidentalhotels.com%2Fcity-hotel%2Foccidental-el-embajador" target="_blank" rel="nofollow"> <img src="http://ti.tradetracker.net/?c=5516&m=191741&a=143420&r=&t=html" width="120" height="60" alt="Occidental hotels, Santo Domingo" /></a> </div>
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<div class="dest">
<ul>
<li><a href="#att9">ZONA COLONIAL</a></li>
<li><a href="#att2">COLUMBUS LIGHTHOUSE</a></li>
<li><a href="#att3">PARQUE MIRADOR SUR</a></li>
<li><a href="#att4">LOS TRES OJOS</a></li>
<li><a href="#att0">BACK TO TOP</a></li>
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<div class="normal1"> Don't get caught!
<p><span><a href="/">Travel Secrets</a></span></p>
unravelled</div>
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<div class="dest dest2">
<ul>
<li><a href="#att9">ZONA COLONIAL</a></li>
<li><a href="#att1">MALECON</a></li>
<li><a href="#att3">PARQUE MIRADOR SUR</a></li>
<li><a href="#att4">LOS TRES OJOS</a></li>
<li><a href="#att0">BACK TO TOP</a></li>
</ul>
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<div class="dest dest3">
<ul>
<li><a href="#att9">ZONA COLONIAL</a></li>
<li><a href="#att1">MALECON</a></li>
<li><a href="#att2">COLUMBUS LIGHTHOUSE</a></li>
<li><a href="#att4">LOS TRES OJOS</a></li>
<li><a href="#att0">BACK TO TOP</a></li>
</ul>
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<div class="dest dest4">
<ul>
<li><a href="#att0">BACK TO TOP</a></li>
<li><a href="#att9">ZONA COLONIAL</a></li>
<li><a href="#att1">MALECON</a></li>
<li><a href="#att2">COLUMBUS LIGHTHOUSE</a></li>
<li><a href="#att3">PARQUE MIRADOR SUR</a></li>
</ul>
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<h2><b>Sightseeing in Santo Domingo</b></h2>
<p>
<h4 id="att9">Zona Colonial</h4>
<p>The Colonial Zone offers a lot to see.</p>
<p>It was near this place, on the eastern side of the Ozama River that, in 1496, Bartholomew Columbus, the brother of Christopher Columbus, founded what became the first settlement in the Americas to have been inhabited to this day. In 1502, the settlement was destroyed by a hurricane and Nicholás de Ovando, Bartholomew’s successor, rebuilt Santo Domingo on its present site, on the other bank of the Ozama River. Its layout became a blueprint for many New World cities.</p>
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<div class="img-container"><img src="/Americas/DomRepublic/images/ZonaColon2.jpg" title="Zona Colonial" alt="The Zone Colonial of Santo Domingo"></div>
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<div class="credit"> <a href="richie2.html" target="_blank" >Photography by Richie Diesterheft</a> </div>
<p> One of the oldest structures in the Colonial Zone is Casa del Cordón. Built in 1502, it was the home of Diego Colón, the son of Columbus and the viceroy of the Spanish colony. He lived there until the completion of the Alcázar (1510-1514), which became, then, the new viceroy’s residence. The Alcázar was thoroughly restored in 1957 and, nowadays, displays a collection of items owned by the Governors overseeing the colony in the period from 16th to the 19th centuries. Of particular interest is the 16th century furnishings and other belongings of Diego Colón and his wife Maria de Toledo.</p>
<p> The street where Doña Maria used to promenade with her court ladies received the name Calle de las Damas. On this street stands the Ozama Fort, another old structure of the Colonial Area. The fort is claimed to be the oldest military fortification in the Americas. Inside, the 18,5 meter tall Torre del Homenaje (the Homage Tower) was named to honor the conquest of Hispaniola – the name of the island shared between the Dominican Republic and Haiti.</p>
<p>The fort and the tower have a dual symbolic meaning. First, because it was from this fort that numerous expeditions of conquest began: Hernán Cortés, to México; Diego Velásquez, to Cuba; Francisco Pizarro, to Peru; Alonso de Hojeda, to Venezuela; Vasco Núñez de Balboa, to Panama; and Ponce de León, to Puerto Rico. And second, because the Homage Tower displays the flags of those nations that attempted to dominate this country: Spain, England, France, (Greater) Colombia, Haiti and the USA. From the top of the tower opens a spectacular view towards the Caribbean coast, and the entrance to the Ozama River. </p>
<p>The major attraction in the Colonial Zone is the, predominantly Gothic Cathedral of Santa María la Menor. Built of solid limestone in the period 1514-1544, it is the first cathedral in the Americas. The Dominicans claim that the relics of Columbus were kept here until recently, when they were transferred, in 1992, to a place specially designed for the purpose in the Faro a Colón - the Columbus Lighthouse (see below).</p>
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<div class="img-container"><img src="/Americas/DomRepublic/images/ParqueColon2.jpg" title="Parque Colon" alt="Parque Colon in Santo Domingo"></div>
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<div class="credit"> <a href="richie.html" target="_blank" >Photography by Richie Diesterheft</a> </div>
<div class="back"> <a href="#att9">BACK TO TOP</a> </div>
<h4 id="att1">Malecón</h4>
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<div class="img-container"><img src="/Americas/DomRepublic/images/malecon.jpg" title="The >Malecón in Santo Domingo" alt="The Malecón in Santo Domingo"></div>
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<div class="credit"> <a href="bunker.html" target="_blank" >Photography by bunkerglosiempre</a> </div>
<p>The Malecón (the word means "a sea wall") stretches along the George Washington Avenue running the length of the Santo Domingo’s oceanfront, from the port near the Colonial Zone. The Malecon is a popular place for leisurely walks, particularly on Sundays when the traffic is diverted from this area to give the space to pedestrians.
Along this waterfront boulevard there are several large hotel and casino complexes, and plenty of small restaurants, clubs and cafes.</p>
<p>The Malecón is also a favourite place for romantic rides in an old-style horse carriage. Many large events in the city life happen on the Malecón, throughout the year, and include the Carnival in February-March, or the Merengue Festival in the last week of July, and the first week of August (but check the dates, as they may change). The Merengue is a lively Caribbean dance with its origins in the island of Hispaniola. It is the equivalent of the Cuban rumba or the Brazilian samba, with its roots in the cultural heritage of the African slave population that came to the island during the colonization period.</p>
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<h4 id="att2">Columbus Lighthouse</h4>
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<div class="img-container"><img src="/Americas/DomRepublic/images/faro.jpg" title="Columbus Lighthouse, Santo Domingo" alt="Columbus Lighthouse, Santo Domingo"></div>
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<div class="credit"> <a href="daniel.html" target="_blank" >Photography by Daniel Lobo</a> </div>
<p>The Columbus Lighthouse (Faro a Colón) is a huge monument to Christopher Columbus, built in 1992, to commemorate the 500th anniversary of the island’s discovery. The remains of the great explorer were removed, on that occasion, from the Santa Maria Cathedral and placed in the lighthouse. This immense memorial is 210 metres long, 34 metres wide, and 46 metres high. There are 157 beams of light radiating skywards from this monumental lighthouse. They can be seen at great distances. It is clamed that often, even reaching the island of Puerto Rico, over 300 Km away. </p>
<p>There is a museum here with displays from different countries, which were influenced by Columbus’s discoveries, European colonization, and evangelization of the Americas. The museum is closed on Mondays.</p>
<div class="back"> <a href="#att9">BACK TO TOP</a> </div>
<h4 id="att3">Parque Mirador Sur</h4>
<p>The Parque Mirador Sur is in the western part of the city. This beautiful park is near the Avenida Anacaona, the place where most of the embassies are. The park is popular spot for daily walks, jogging, roller-skating and cycling. The park has stone caverns that in pre-Columbian days were inhabited by Taínos, the local Indian people. One of those caverns was currently transformed into the popular discotheque “La Guacara Taína“. The place is worth a visit to appreciate its exuberant interior and for the shows and events that are staged there.</p>
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<h4 id="att4">Los Tres Ojos</h4>
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<div class="img-container"><img src="/Americas/DomRepublic/images/3ojos.jpg" title="The Three Eyes caves, Santo Domingo" alt="The Three Eyes caves, Santo Domingo"></div>
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<div class="credit"> <a href="moises.html" target="_blank" >Photography by Moises Terrero</a> </div>
<p>In a different part of town, about ten kilometres from the city centre, the Parque Mirador Este is known for its natural lime stone caverns filled with water. The lagoons, poetically called "ojos" make up the “Tres Ojos” (three eyes). These once subterranean lagoons collapsed to form and expose small open-air lakes. They contain water of varied and vivid colours, which drain into the lakes from underground currents. Usually, the visit starts with Laguna Azul that has sky blue water; the next lake to visit is Lago del Frigorifico (Fridge Lake). The name is due to its waters having a constant temperature of +2° C. For an extra fee, the lakes and lagoons in the park can be crossed by boat. The third lake leads visitors to a beautiful stalactite grotto with views over the lush tropical forest. The place was recently used as the setting for Tarzan movies.</p>
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I’ll post the styles in another post because it goes over the character limit of this post so just grab the styles and then insert then in style tags of the above html so you can test. Then save it and then run it in your browser.
You will see how the columns all match without any heights and the code is about 50% lighter than your code. I have made some design tweaks to keep things simpler (such as not letting the middle column go flush with the top and bottom) but in my opinion that makes it look neater although with a few tweaks we could probably achieve your design.
There is no need to continually repeat styles for elements that are the same. e.g. Your panels in the left side all had ids and you applied the same 10 or so rules to every one of them and the only difference in some of them was a different margin. All you needed was one class with all the common styles and then just add an extra class when you need to modify the elements. That save over 90% of the code you used for those elements.
I also tweaked the main nav so it doesn’t disappear and scales better across the range.
This could still be tidied up more but just wanted to show what could be done in 30 minutes or so.