diff --git a/ethexe/ethereum/src/router/events.rs b/ethexe/ethereum/src/router/events.rs
index ce67e48d491..b8c29781673 100644
--- a/ethexe/ethereum/src/router/events.rs
+++ b/ethexe/ethereum/src/router/events.rs
@@ -16,10 +16,11 @@
 // You should have received a copy of the GNU General Public License
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
-use crate::{decode_log, IRouter};
+use crate::{abi::utils::bytes32_to_h256, decode_log, IRouter};
 use alloy::{primitives::B256, rpc::types::eth::Log, sol_types::SolEvent};
 use anyhow::{anyhow, Result};
 use ethexe_common::events::{RouterEvent, RouterRequestEvent};
+use gprimitives::H256;
 use signatures::*;
 
 pub mod signatures {
@@ -89,3 +90,13 @@ pub fn try_extract_request_event(log: &Log) -> Result<Option<RouterRequestEvent>
 
     Ok(Some(request_event))
 }
+
+pub fn try_extract_committed_block_hash(log: &Log) -> Result<Option<H256>> {
+    if log.topic0() != Some(&BLOCK_COMMITTED) {
+        return Ok(None);
+    }
+
+    decode_log::<IRouter::BlockCommitted>(log)
+        .map(|e| Some(bytes32_to_h256(e.hash)))
+        .map_err(Into::into)
+}
diff --git a/ethexe/observer/src/observer.rs b/ethexe/observer/src/observer.rs
index 3fa8d2dbbed..fdca71af5df 100644
--- a/ethexe/observer/src/observer.rs
+++ b/ethexe/observer/src/observer.rs
@@ -25,7 +25,7 @@ use std::{collections::HashMap, sync::Arc};
 use tokio::sync::watch;
 
 /// Max number of blocks to query in alloy.
-pub(crate) const MAX_QUERY_BLOCK_RANGE: u64 = 100_000;
+pub(crate) const MAX_QUERY_BLOCK_RANGE: usize = 1024;
 
 pub(crate) type ObserverProvider = RootProvider<BoxTransport>;
 
@@ -273,7 +273,7 @@ pub(crate) async fn read_block_events_batch(
     let to_block = to_block as u64;
 
     while start_block <= to_block {
-        let end_block = to_block.min(start_block + MAX_QUERY_BLOCK_RANGE - 1);
+        let end_block = to_block.min(start_block + MAX_QUERY_BLOCK_RANGE as u64 - 1);
 
         let filter = Filter::new().from_block(start_block).to_block(end_block);
 
@@ -385,8 +385,9 @@ pub(crate) async fn read_block_request_events_batch(
     let mut start_block = from_block as u64;
     let to_block = to_block as u64;
 
+    // TODO (breathx): FIX WITHIN PR. to iters.
     while start_block <= to_block {
-        let end_block = to_block.min(start_block + MAX_QUERY_BLOCK_RANGE - 1);
+        let end_block = to_block.min(start_block + MAX_QUERY_BLOCK_RANGE as u64 - 1);
 
         let filter = Filter::new().from_block(start_block).to_block(end_block);
 
@@ -476,6 +477,54 @@ async fn read_request_events_impl(
     Ok(res)
 }
 
+pub(crate) async fn read_committed_blocks_batch(
+    from_block: u32,
+    to_block: u32,
+    provider: &ObserverProvider,
+    router_address: AlloyAddress,
+) -> Result<Vec<H256>> {
+    let mut start_block = from_block as u64;
+    let to_block = to_block as u64;
+
+    let mut res = Vec::new();
+
+    while start_block <= to_block {
+        let end_block = to_block.min(start_block + MAX_QUERY_BLOCK_RANGE as u64 - 1);
+
+        let filter = Filter::new().from_block(start_block).to_block(end_block);
+
+        let iter_res = read_committed_blocks_impl(router_address, provider, filter).await?;
+
+        res.extend(iter_res);
+
+        start_block = end_block + 1;
+    }
+
+    Ok(res)
+}
+
+async fn read_committed_blocks_impl(
+    router_address: AlloyAddress,
+    provider: &ObserverProvider,
+    filter: Filter,
+) -> Result<Vec<H256>> {
+    let filter = filter
+        .address(router_address)
+        .event_signature(Topic::from(router::events::signatures::BLOCK_COMMITTED));
+
+    let logs = provider.get_logs(&filter).await?;
+
+    let mut res = Vec::with_capacity(logs.len());
+
+    for log in logs {
+        if let Some(hash) = router::events::try_extract_committed_block_hash(&log)? {
+            res.push(hash);
+        }
+    }
+
+    Ok(res)
+}
+
 #[cfg(test)]
 mod tests {
     use std::time::Duration;
diff --git a/ethexe/observer/src/query.rs b/ethexe/observer/src/query.rs
index 0f7221bacd8..60fd4bc1c7b 100644
--- a/ethexe/observer/src/query.rs
+++ b/ethexe/observer/src/query.rs
@@ -1,20 +1,16 @@
-use std::{
-    collections::{BTreeSet, HashMap, VecDeque},
-    sync::Arc,
-};
-
 use crate::{
     observer::{
         read_block_events, read_block_request_events, read_block_request_events_batch,
-        read_code_from_tx_hash, ObserverProvider,
+        read_code_from_tx_hash, read_committed_blocks_batch, ObserverProvider,
+        MAX_QUERY_BLOCK_RANGE,
     },
     BlobReader,
 };
 use alloy::{
-    eips::BlockNumberOrTag,
+    network::{Ethereum, Network},
     primitives::Address as AlloyAddress,
     providers::{Provider, ProviderBuilder},
-    rpc::types::eth::BlockTransactionsKind,
+    rpc::{client::BatchRequest, types::eth::BlockTransactionsKind},
 };
 use anyhow::{anyhow, Result};
 use ethexe_common::{
@@ -22,7 +18,12 @@ use ethexe_common::{
     events::{BlockEvent, BlockRequestEvent, RouterEvent},
 };
 use ethexe_signer::Address;
+use futures::future;
 use gprimitives::{CodeId, H256};
+use std::{
+    collections::{BTreeSet, HashMap, VecDeque},
+    sync::Arc,
+};
 
 /// Height difference to start fast sync.
 const DEEP_SYNC: u32 = 10;
@@ -95,6 +96,55 @@ impl Query {
             .collect())
     }
 
+    async fn batch_get_block_headers(
+        provider: ObserverProvider,
+        database: Arc<dyn BlockMetaStorage>,
+        from_block: u64,
+        to_block: u64,
+    ) -> Result<Vec<(H256, BlockHeader)>> {
+        log::debug!("Querying blocks from {from_block} to {to_block}");
+
+        let mut batch = BatchRequest::new(provider.client());
+
+        let handles: Vec<_> = (from_block..=to_block)
+            .map(|bn| {
+                batch
+                    .add_call::<_, Option<<Ethereum as Network>::BlockResponse>>(
+                        "eth_getBlockByNumber",
+                        &(format!("0x{bn:x}"), false),
+                    )
+                    .expect("infallible")
+            })
+            .collect();
+
+        batch.send().await?;
+
+        let blocks: Vec<_> = future::join_all(handles).await;
+
+        let mut res = Vec::with_capacity(blocks.len());
+
+        for block in blocks {
+            let block = block?.ok_or_else(|| anyhow!("Block not found"))?;
+            let block_hash = H256(block.header.hash.0);
+
+            let height = block.header.number as u32;
+            let timestamp = block.header.timestamp;
+            let parent_hash = H256(block.header.parent_hash.0);
+
+            let header = BlockHeader {
+                height,
+                timestamp,
+                parent_hash,
+            };
+
+            database.set_block_header(block_hash, header.clone());
+
+            res.push((block_hash, header))
+        }
+
+        Ok(res)
+    }
+
     /// Populate database with blocks using rpc provider.
     async fn load_chain_batch(
         &mut self,
@@ -102,59 +152,52 @@ impl Query {
         to_block: u32,
     ) -> Result<HashMap<H256, BlockHeader>> {
         let total_blocks = to_block.saturating_sub(from_block) + 1;
-        log::info!("Starting to load {total_blocks} blocks from {from_block} to {to_block}");
 
-        let fetches = (from_block..=to_block).map(|block_number| {
-            let provider = self.provider.clone();
-            let database = Arc::clone(&self.database);
-            tokio::spawn(async move {
-                let block = provider
-                    .get_block_by_number(BlockNumberOrTag::Number(block_number as u64), false)
-                    .await?;
-                let block = block
-                    .ok_or_else(|| anyhow!("Block not found for block number {block_number}"))?;
-
-                let height = u32::try_from(block.header.number)
-                    .map_err(|err| anyhow!("Ethereum block number not fit in u32: {err}"))?;
-                let timestamp = block.header.timestamp;
-                let block_hash = H256(block.header.hash.0);
-                let parent_hash = H256(block.header.parent_hash.0);
+        log::info!("Starting to load {total_blocks} blocks from {from_block} to {to_block}");
 
-                let header = BlockHeader {
-                    height,
-                    timestamp,
-                    parent_hash,
-                };
+        let headers_handles: Vec<_> = (from_block..=to_block)
+            .step_by(MAX_QUERY_BLOCK_RANGE)
+            .map(|start| {
+                let end = (start + MAX_QUERY_BLOCK_RANGE as u32 - 1).min(to_block);
 
-                database.set_block_header(block_hash, header.clone());
+                let provider = self.provider.clone();
+                let database = self.database.clone();
 
-                Ok::<(H256, BlockHeader), anyhow::Error>((block_hash, header))
+                tokio::spawn(async move {
+                    Self::batch_get_block_headers(provider, database, start as u64, end as u64)
+                        .await
+                })
             })
-        });
+            .collect();
+
+        let headers_fut = future::join_all(headers_handles);
 
-        // Fetch events in block range.
-        let mut blocks_events = read_block_request_events_batch(
+        let events_fut = read_block_request_events_batch(
             from_block,
             to_block,
             &self.provider,
             self.router_address,
-        )
-        .await?;
+        );
+
+        let (headers_batches, maybe_events) = future::join(headers_fut, events_fut).await;
+        let mut events = maybe_events?;
+
+        let mut res = HashMap::with_capacity(total_blocks as usize);
 
-        // Collect results
-        let mut block_headers = HashMap::new();
-        for result in futures::future::join_all(fetches).await {
-            let (block_hash, header) = result??;
-            // Set block events, empty vec if no events.
-            self.database.set_block_events(
-                block_hash,
-                blocks_events.remove(&block_hash).unwrap_or_default(),
-            );
-            block_headers.insert(block_hash, header);
+        for batch in headers_batches {
+            let batch = batch??;
+
+            for (hash, header) in batch {
+                self.database
+                    .set_block_events(hash, events.remove(&hash).unwrap_or_default());
+
+                res.insert(hash, header);
+            }
         }
-        log::trace!("{} blocks loaded", block_headers.len());
 
-        Ok(block_headers)
+        log::trace!("{} blocks loaded", res.len());
+
+        Ok(res)
     }
 
     pub async fn get_last_committed_chain(&mut self, block_hash: H256) -> Result<Vec<H256>> {
@@ -186,9 +229,16 @@ impl Query {
         };
 
         let mut chain = Vec::new();
-        let mut committed_blocks = Vec::new();
         let mut headers_map = HashMap::new();
 
+        let committed_blocks = read_committed_blocks_batch(
+            latest_valid_block_height + 1,
+            current_block.height,
+            &self.provider,
+            self.router_address,
+        )
+        .await?;
+
         if is_deep_sync {
             // Load blocks in batch from provider by numbers.
             headers_map = self
@@ -218,7 +268,6 @@ impl Query {
             }
 
             log::trace!("Include block {hash} in chain for processing");
-            committed_blocks.extend(self.get_committed_blocks(hash).await?);
             chain.push(hash);
 
             // Fetch parent hash from headers_map or database